The first game[s] I ever owned for my SNES and it was pretty darn good.
Super Mario World is an excellent 2D side-scroller and still is fun to play today. There's tons of features available on it like gliding, throwing fireballs, riding Yoshi and co., becoming temporarily invisible, smashing obstacles, capturing a pair of wings for a bonus level, and more. If you haven't played this game, it's definitely worth a try.
And the original Mario Brothers remakes are all outstanding as well. The levels are pretty much identical to the originals, except all the sprites and backgrounds and characters are all redrawn for then-modern consoles. These games started the best-selling franchise of all time.
The gameplay is legendary, you just can't get more classic than these. My advice is, if you have never played these games enough, you need to. You don't know what you are missing.