Naruto doesn't remember his dreams. Not that that is unusual, of course. Most people don't realize that they dream every night and only remember a few, what few and why is one of life's unanswered questions.
Before that fateful night with Iruka--the one when Naruto found out about himself and discovered that people cared for him anyway--Naruto's dreams had been dark, filled with screams and shouts and blood. But that didn't matter, since he didn't remember them anyway. The only ones he remembered were the safe ones, the ones about pranks he would pull and about his plans for the future, gaining the Hokage title and rubbing it in the faces of his doubters, which included pretty much everyone. Perhaps he didn't remember the bad dreams because his psyche--still that of a child, no matter how mature he could be at times--would not let him. Or perhaps, in a moment of mercy, the Kyuubi itself blocked the dreams--which were its memories--from entering and destroying the boy's mind. Whatever the reason, however it happened, Naruto did not remember his bad dreams.
After that night, though, once Naruto became a Gennin ninja, his dreams became more…specific. Instead of rubbing his success in the blank faces of unknown villagers, he now had a target: Uchiha Sasuke. His dreams consisted of him defeating the evil--for the other boy was always evil in those dreams--Sasuke and saving the princess Sakura. Sometimes Kakashi made an appearance, sometimes he didn't.
Those dreams did not last long, however, as Naruto--though he'd never admit it--felt his friendship with the dark-haired boy growing. Now his nighttime visions held images of him saving both Sasuke and Sakura--and sometimes Kakashi--from some faceless evil--that happened to have nine-tails.
Later, after the incident in the Wave Country, Naruto's dreams would sometimes host a smiling Haku, or the image of Sasuke's 'death,' or Haku's, or Zabuza's…needless to say, the boy enjoyed these dreams much less than the others that he was able to remember. As far as he knew, until that incident, he had never had what someone might call a 'nightmare.' He couldn't remember the screams he'd grown up hearing.
After that, it seemed that the path had been paved for all sorts of nightmares. Now, instead of sleeping peacefully, most of his nights were spent wrestling with images of his friends dying, of them hating him because of the Kyuubi, or worse, because he failed them. He tosses and turns now, more than he ever did because of the faceless screams with which he had grown up. It's worse now, because he knows and cares about the screamers, and, most horribly, because he remembers. The Kyuubi can't block the images of the things he's already seen. When he lays down, it is images of Lee's crushed body he sees, of a snake heading towards Sasuke, of Sakura trapped against a tree, of Sasuke--his best friend, only this isn't really Sasuke, is it?--coming at him with aChidori and a demonic look in his eye. And this time, he is unable to save them, unable to get Tsunande, to block the snake, or defeat Gaara, unable to…well, that time he was unable to act anyway.
And then he wakes up, and it's one of the only times that he's happy to be alone, because he wouldn't want anyone to see him like that, drenched in sweat, heart pounding, eyes--though he never sees this--a brilliant scarlet. And, being Naruto, he smiles, and takes a deep breath--it's not real, it's not real, it's not real--and turns over. He pretends, to himself, that he is going back to sleep, but in reality--horrible reality--he will lie there the rest of the night, staring out his window at the sleeping village. And, being Naruto, he will vow to himself that he will never ever fail anyone again. And, being Naruto, he will do his best to keep that promise.