I never found Zelda dungeons to be ridiculously hard until I played Majora's mask. Sure, there were rooms in many of the dungeons of the other games that confused me, but it would usually be something that i just missed that was supposed to be obvious, and it would only happen once or twice per game. I first had trouble with the water temple in Majoras Mask (definitely harder then the one in OOT, that was just annoying). However the Stone Temple Dungeon was definitely the hardest. I went through that dungeon more times than I can count, in my determination to beat it without a guide, which failed miserably. I still have yet to beat it to this day, but I keep on trying to this very day, and I plan on getting back to it now that I beat Skyward Sword.