1st HokageName: Unknown (Referred to as Shodai Hokage)
Strengths: Herculean Strength, Secret tree Jutsu
Family Members: The 2nd Hokage (Brother), Tsunade (Granddaughter), and Nawaki (Grandson)
Students: Sarutobi the 3rd Hokage (Deceased), Homura, and Koharu the Hokage's advisors
Info: Sixty years ago, Shodai Hokage led a group of Shinobi to a lush forest land and founded the village of Konoha. Unfortunately during that chaotic era, he passed away shortly after the creation of the village. He later returned in the series when Orochimaru resurrected him using the Impure World Resurrection (Kyuchiyose Edo Tensei) and was forced to fight his former disciple. The 3rd had to stop his former teacher and used the 4th's Demonic Soul Seal (Fuuinjutsu Shiki Fuujin) sealing his soul into one of his Kage Bunshins. With this jutsu, whoever's soul is sealed will suffer for all eternity in the belly of the Shinigami, never gaining release, hating each other and battling for all of eternity. Shodai Hokage's fighting style is a direct one, preferring to attack the opponent head on in hand to hand combat rather than attack from a distance or rely on jutsus to do his dirty work. Sadly because of this, we only see him use one jutsu. The Secret Tree Element Technique: Birth of the Trees (Mokuton Hijutsu, Jukai Koutan), is a secret technique that (allegedly) only he could use and a number of the large trees growing in Konoha were created with this technique. By using his chakra as a source of life, Shodai Hokage can cause massive trees to grow exponentially fast as well as control their movement whilst they grow. This is particularly useful for ensnaring opponents or wrecking buildings and is truly one of the coolest jutsus ever. When Orochimaru discovered that only those with the bloodline of the 1st Hokage could control Bijuu, he decided to break into the grave of the 1st and steal his DNA. He then implanted the DNA into 52 test children. Only one survived as a clone of the 1st and his name was Yamato.
2nd HokageName: Unknown (Referred to as Nidaime Hokage)
Strengths: Genjutsu, Water Style Jutsus, Agility
Family Members: The 1st Hokage (Brother), Tsunade (Grandniece), and Nawaki (Grandnephew)
Students: Sarutobi the 3rd Hokage (Deceased), Homura, and Koharu the Hokage's advisors
Info: The cofounder and creator of the Konoha, he was the 2nd Hokage. He is the younger brother of the 1st Hokage and took over the role of Hokage when his brother stepped down. Nidaime inherited his older brother's will and was responsible for the creation of the Ninja Academy and others organizations within the village. The great ninja war broke out afterwards; in his dying moment, Nidaime instructed the future generation to pacify the war and ensure the village's prosperity. He later returned in the series when Orochimaru resurrected him using the Impure World Resurrection (Kyuchiyose Edo Tensei) and was forced to fight his former disciple. The 3rd had to stop his former teacher and used the 4th's Demonic Soul Seal (Fuuinjutsu Shiki Fuujin) sealing his soul into one of his Kage Bunshins. In contrast to his brother, who prefers to assault the enemy head on, Nidaime is a more nimble fighter preferring to capitalize on his speed and agility to catch his opponents off guard. He is also very dangerous at a distance thanks to his prowess with Water Style techniques, and he can even use extremely powerful water attacks in areas with no water nearby, a feat that has yet to be repeated.
3rd HokageName: Sarutobi
Strengths: Knowledge of over 1,000 Jutsus, Genius intelligence, Summoning
Family Members: Konohamaru (Grandson), Asuma Sarutobi (Son)
Students: Jiraiya, Tsunade, and Orochimaru
Info: Sarutobi is a kind old man in every sense of the word; he regards everyone living in Konoha has a family member often acting like a grandfather to his people instead of just their leader. His biggest drive in life is to keep Konoha safe and to keep the people who live there happy. He is also known to be a bit of a pervert as seen by his vulnerability to Naruto's Sexy Jutsu as well as his interest in young Jiraiya's peeping techniques. Despite his calm and kindly exterior however, he is an incredibly strong leader with guts and willpower to match. Not much is known about Sarutobi's life before he became Hokage. We do know that as a Jounin he was in charge of training the Gennins that would one day become the 2 Legendary Sennins, Jiraiya, Tsunade, and Orochimaru, and that he pioneered the "get the bells" drill the Kakashi would later employ on Naruto and the rest of team seven. After the 4th Hokage was chosen he decided to retire and let the 4th run the village, but after the 4th died fighting Kyuubi Sarutobi took the position of Hokage once again. It was because of his leadership skills that lead Konoha to victory and peace against both the Earth and Thunder countries. He took great interest in Orochimaru as a student because of Orochimaru's genius and hoped he would someday inherit the title of Hokage and rule the village justly. This dream blinded him from seeing Orochimaru's inner malice until one day Orochimaru was caught experimenting on Konoha ninjas trying to create in immortality jutsu. Even when confronted by this evidence, Sarutobi still couldn't bring himself to kill his former student and Orochimaru escaped to wreck havoc later. Prior to the Wind and Sound country's invasion of Konoha he was planning on staying in office for 5 more years before choosing a 5th Hokage, but that plan was never realized do to his defeat at Orochimaru's hands, but even in defeat the 3rd managed to save his homeland by stealing the life-force from Orochimaru's hands which rendered them useless, and him jutsu-less. Being a master of over 1,000 jutsus, including every secret jutsu in Konoha, Sarutobi has a pretty nice arsenal of moves to choose from, though he seems to favor fire and earth style jutsus. This is most likely due to the fact the fire jutsus are Konoha's specialty and the fact that he spent a great deal of time fighting against enemy ninjas from the earth country, thus he has a great deal of experience with them. But his arsenal alone is not what makes him so dangerous, it's the way he uses and combines them that lead to him being called the most powerful Hokage of all time (at least, when he was in his prime). An example of this was seen in his fight with Orochimaru wherein he combined the Earth Style; Earth Dragon Missile (Doton, Doryuudan), a jutsu that causes a dragon head of mud to rise up and spit mud missiles at the opponent, with the Fire Dragon Missile (Karyuudan) which causes the user to breath intends flames, to create missiles of molten lava. Like most upper level Shinobis, Sarutobi also knows the Summoning Jutsu (Kyuichose No Jutsu); in his case he is able to summon monkeys. The only one of whom we've seen him summon (and most likely the strongest of the monkeys) is Enma, the eldest Monkey a.k.a. The Monkey God, King Enma. While he's not as large as some of the other Kyuichose No Jutsu animals, Enma's extremely tough, as he is able to physically fend off a Kage level opponent without too much difficulty. His true power though, is his unique ability to transform into a black and gold Bo staff called the "Free Forming Diamond pole," (Kongou Nyoi). As its name suggests this weapon is as hard as a diamond and can adjust its size and length at will. not only that, but since Enma is the actual weapon itself he/it can move around completely unaided, he can also multiply himself and cause his eyes and arms to sprout from anywhere on the pole. As a last resort Sarutobi has the ability to call on the most power and most dangerous jutsu created by the 4th Hokage, the Demonic Soul Seal (Fuuinjutsu Shiki Fuujin). This is the same technique the 4th used to seal Kyuubi inside Naruto's body so the sheer power of this jutsu is beyond compare. This Jutsu allows the user to call upon a Shinigami or "Death God" which joins with the actions of the user. Shinigami reaches into an outline of a soul in front of him which is actually the user. When the user grabs the victim, the Shinigami extends his hand through the soul outline and comes out from the stomach of the user. The Shinigami's hand goes into the enemy's stomach where from it literally rips the soul out. After the soul is pulled back into the user, the user says "Fuuin" (Seal) this completes the seal of the soul in the user's body. This can be used until the user runs out of energy, and since it is a sealing jutsu, there is a price. The user pays the price with his life, which death devours. The souls of both the user and the target are kept in the belly of the Shinigami, and will suffer for all eternity in the belly of the Shinigami never gaining release, hating each other and battling for all of eternity. Apparently if the soul is not completely extracted from the body, Death can cut part of it and seal just the part which he has grasped. In Orochimaru's case this was his arms, which are now lifeless and unusable.
4th HokageName: Namikaze Minato
Strengths: Speed, Rasengan
Family Members: Naruto Uzumaki, Uzumaki Kushina
Students: Kakashi Hatake, Rin, Obito Uchiha
Info: Sadly we haven't seen much of this Konoha legend in action so most info on him comes from the testimony of other characters in the story. All we really know about Minato is that he was the Jounin who trained Kakashi and that he was the one who defeated Kyuubi by sealing him inside Naruto's body. The most dangerous thing about Minato was his insane speed gained thanks to his Body Flicker Jutsu (Shunshin no Jutsu). This jutsu instantly transports him to anyplace he wants, hence the nickname "Yellow Flash of Konoha" and can be used over long distances as long as he knows exactly where he's going. Another jutsu that Minato uses involes special kunais. These kunais are made so wherever they are throw, the 4th Hokage can immediately teleport to its location. This technique is particularly effective on large numbers of enemies; Minato will simply distribute his special kunai to ally ninja and tell them to throw them at different targets at the same time, then simply teleport to the location and finish off his opponents. This attack can literally defeats a whole army almost instantly. Minato is also one of only four people in the Naruto world able to use the Rasengan, as well as its creator. While we don't know the peculiars of the Rasengan's birth, we do know it took Minato three years to perfect the technique. Based on Gamabunta's testimony we also know that Minato was able to use the Summoning Jutsu (Kyuichose No Jutsu) to summon frogs just like his teacher. As a last resort Minato has the ability to call on the most power and most dangerous Jutsu that he himself created, the Demonic Soul Seal (Fuuinjutsu Shiki Fuujin), the Jutsu that sealed Kyuubi inside Naruto. This Jutsu allows the user to call upon a Shinigami or "Death God" which joins with the actions of the user. Shinigami reaches into an outline of a soul in front of him which is actually the user. When the user grabs the victim, the Shinigami extends his hand through the soul outline and comes out from the stomach of the user. The Shinigami's hand goes into the enemy's stomach where from it literally rips the soul out. After the soul is pulled back into the user, the user says "Fuuin" (Seal) this completes the seal of the soul in the user's body. This can be used until the user runs out of energy, and since it is a sealing Jutsu, there is a price. The user pays the price with his life, which death devours. The souls of both the user and the target are kept in the belly of the Shinigami, and will suffer for all eternity in the belly of the Shinigami never gaining release, hating each other and battling for all of eternity. However in the 4th's case he somehow moved Kyuubi's soul into Naruto's body instead of into the Shinigami's stomach, it is presently unknown exactly how he accomplished this, but it's a good thing he did.