Nintendo 64 for me. First console my family ever bought, and a lot of childhood memories were on that very system. The nights I never finished my homework because of it! Love you Nintendo 64.
Sarcasm? Got to be the SNES. NES and N64 had some good titles but I thought there were more crap than good on them, or the crap outweighed the good. SNES had a very stellar line up, good titles like DKC, the mario games, KI, Pilotwings, Starwing, Super Metroid, all great games that have aged well.