SNES! IGN say it's the best console ever made. It has the best RPG's (when SquareSoft and Nintendo made them right), best platformers, best shooters, best everything. It's also the console Super Mario Kart, and Donkey Kong Country debuted on.
After SNES I'd say N64. A lot of Nintendo's best games released on that console. Best Zelda's, Best Mario Kart (but MK Wii is about as good), best Smash Bros, Best Mario (but again Wii Mario's are just as good), Best Star Fox, Best Mario Party (they used to be awesome!), Goldeneye, Donkey Kong, Banjo Kazooie, Paper Mario, etc.
Lol, my inner Nintendo is showing, but to be honest, SNES-Gamecube are all equally as good. Gamecube re-introduced the most IP's, N64 was the best party system, and SNES had the best classic titles, stuff we rarely see nowdays.