A Link To the Past was the definitive Zelda game, gameplay wise, and it's definitely one of my favorite games.
OoT was too easy, but it had a really nice atmosphere that was worked into the level design. I'm not sure which Zelda I like more.
Most non-action RPG's bore me, but I really loved Earthbound. At its core it's a very archaic system, but the mixture of the whole environment, story presentation, and rolling odometers kept me hooked.
Starcraft is my favorite RTS and I'm still playing it (mostly due to the online community) after 3 or so years.