Well, I'm torn between Oncarina of Time and Twilight Princess as my favorite. Oncarina of time I think had the best game play in general because of all the temples. But I played it a lot and have beat it quite a few times. Twilight Princess I love the graphics and the videos. I have not yet got it for the Wii, only on Gamecube, but I'm hoping to get it soon.

As for the temples. It doesn't matter what Zelda game it is (or Mario for that matter) the Water Temple/Level is always the hardest...or the most tedious anyways lol.