5. The Legend of Zelda: Majora's Mask - N64
One of Nintendo's darkest and most conceptually ambitious offerings to date, Majora's Mask didn't quite "wow" me as much as a certain other Zelda game, that may or may not be on this list later on, but damn, is it still fantastic.
While Termina wasn't as expansive as Hyrule, it certainly was more detailed. NPCs weren't glued to the ground, or aimlessly wandering around. They had a schedule, a purpose, and a story to tell, if you dug deep enough. Side-quests were more numerous than ever, with some of them being amongst the lengthiest and most in-depth in the Zelda series. The tone was refreshingly darker, the masks were just plain awesome to use, and the music, while mostly recycled from Ocarina, was nevertheless top-notch.
If Majora's Mask had a better saving system, I would proclaim it as the best Zelda without hesitation. But since it doesn't... Sorry, Majora. You'll have to be satisfied with being just one of the best games ever created.