Voted for Forest, not because it was the biggest or the best (though it is pretty damn good!) but because it was the first as adult link. The whole lead up to it, seeing Ganon's corruption of beautiful Hyrule, how the Kokiri were being terrorised and locked in their homes.
What a jerk Ganon really is hit me for the first time (was 12 years old or something like?) when you go out to one of the gardens inside the temple and it's got spiders crawling EVERYWHERE. This was a paradise, bastion to the power of the sage of the forest, and the bastard is all up in here with his spiders. Not cool man, not cool.