I hate the minigames, the rewards are always just a bit out of reach for me. The only one I can do pretty well is the rupee shooting in OOT. However, I can only do it on the classic n64 controller.
That's like asking which hemorrhoid is my favorite. If I absolutely HAD to choose, I would say "Them" from Majora's Mask. It wasn't terribly difficult (provided you don't try to use Epona) and it was really creepy and cool.