Ah, there's so many but I'd have to say the Metroid-series. Especially the 2D-games. I'm just a sucker for explorative action/rpg-platformers.
Super Metroid is still my absolute favorite game ever.
I would have to say both Metroid and Kirby, as I've found each series to be consistently fun and innovative with each installment. I also really like F-Zero and Star Fox, but it seems their potential has been buried beneath the Nintendo cash cows.
Pok?mon, Mario, Kirby, Zelda. Those are my top four.
I love Pok?mon for it's music and training up teams and breeding for fun. I love Mario just for its randomness. Kirby for its nostalgia and Zelda for its challenge.
Pok?mon, Mario, Kid Icarus, Kirby. Unless you aren't counting the Yoshi games as part of the Mario franchise, then add those to the list. But it's difficult, I like pretty much all the others almost as much.
Pokemon, but I think that I would love Zelda if I played it, I have only played a link to the past, it were a long time ago so i don?t really remember it, I?m planning on playing it again soon, and then buy a link between worlds.