1) Chrono Trigger
2) Final Fantasy III(us)/VI(jap)
3) Killer Instinct
4) Donkey Kong Country 1,2&3
5) Yoshi's Island
6) Star Fox
7) Super Mario World
8) Mega Man X
9) Parodius 1,2&3 (Super Famicom)
10) Uniracers
I wrote this list first, then went on to read the other posts before posting it myself. Just as meppi suggested.
Even though I didn't included certain games from the other lists, I find all the games mentioned here to be top notch. I could go on and on about great SNES games, there were so many of them.
The SNES also received great ports from other plateforms of the time. Super Turrican (Amiga), SimCity (DOS) and Syndicate (DOS) come to mind. I am really glad they released the later two for my SNES because when they came out, my PC was a 8088 with an ASCII-only monochrome card.