Super Mario World for SNES. Best Mario game ever, followed by 64. We used to have hella ROMs, so I played Duke Nukem, Tom and Jerry, Commander Keen, Halloween Harry, etc. My grandparents have a Super Nintendo that still works, and I play it whenever I'm over there.

There was also a series of graphical text adventures (like Zork, but with the action shown on the screen in OMGWTF16COLORS) that I forget the name of... There was one with a haunted house and one with a plane crash in a jungle, and they both seemed to be about saving the main character's girlfriend.