No. Well, not yet, atleast. Naruto does however, use ALL nine tails, when he fights Pain (around chapters 438-443). He starts with 6 tails, then Nagato stops him, and then Naruto uses all nine, but the 4th Hokage entered Naruto's conscience just before Naruto was about to remove the seal, and stops him.
Not necessarily "useless", but he is less powerful without Kyuubi.
Because he has Kyuubi sealed inside him, Naruto has way more stamina than the average ninja, as well as having access to a nearly bottomless supply of chakra. Demon chakra, that is. This leaves him with the ability to defeat anyone he wants but because of his stubborn and kind personality, he doesn't. He could but he's have to risk the possibility that he dies from Kyuubi's chakra or Kyuubi could escape if he uses too much demon chakra. He could beat anyone if he had the heart to.
Kyuubi
Yup. Because of the seal, Naruto doesn't have access to all of Kyuubi power and Kyuubi can easily regenerate all his chakra. He probably has other tricks up his sleeve.
in toys r us
Probably at one time. How else could he have been created?
There was this one time where he got so mad at Orochimaru that his whole skin peeled off and the Kyuubi partially came out making the mini kyuubi, but so far it hasn't.
Almost everyone does already know about Kyuubi. But when everyone sees Naruto using Kyuubi at the most he's ever used it was during the battle with Pain, around chapters 427-444. He goes 6 tails around chapter 436-438, and uses all 9 after that. But he is stopped by someone...
Kyuubi is Japanese word. 'Kyu' means 9 in Japanese. So Kyuubi is 9 tailed
the kyuubi is the nine tailed demon fox yodaime sealed within Naruto.
Not necessarily "useless", but he is less powerful without Kyuubi.
No. Kyuubi strongly resents the fact that the Yondaime managed to seal him.
Chapter 299 was the first time Naruto went kyuubi.
Because he has Kyuubi sealed inside him, Naruto has way more stamina than the average ninja, as well as having access to a nearly bottomless supply of chakra. Demon chakra, that is. This leaves him with the ability to defeat anyone he wants but because of his stubborn and kind personality, he doesn't. He could but he's have to risk the possibility that he dies from Kyuubi's chakra or Kyuubi could escape if he uses too much demon chakra. He could beat anyone if he had the heart to.
Kurama
no
Almost everybody