This is a toughy. The first Mario on the nes was awsome. Couldn't stand Mario 2. Super Mario World on the snes had me hooked for months. Mario Kart I still play, its why my snes is still under my tv next to my 360. For some reason I've never been able to get into Mario 64 and Mario sunshine. They maybe excellent games, just not my cup of tea. Super Mario Bros on the ds is a very good game and goes someway to recapturing the magic. Overall though my vote has to go to Super Mario Brothers 3 on the nes. I played this game constantly. Finding out every secret I could, every hidden block, I was hooked for years, litterally.