Inside Jabu-Jabu's Belly might be one of my favorite dungeons, despite it not making any sense whatsoever (how are his insides so complex and spacious anyway? Jabu-Jabu is nowhere near that big).
It's just so nasty, and I felt so uneasy and grossed out throughout the entire thing (in a good way).
Now I know what Snake means about Princess Ruto, though. She was such a bitch. Actually having to use her as a button block is a cute idea, but I dislike the implications of it (literally objectifying her). And she still bitches every time you leave her alone, even if you're kind of forced to. That was the worst part.
Still a great dungeon, though. Current favorite in OoT. Barinade was a cool boss.