One of the benefits of gaming several generations in the past is that time and criticism have divided the dreck from the best games a console has to offer. Racketboy has put together a list of the best action platformer games from the Sega Genesis era, highlighting favorites such as Sonic the Hedgehog and shining a light on titles you may have missed, such as Ristar, Pulseman, and *gasp* a game featuring Mickey Mouse.
While I didn't have a Genesis when I was a kid, I did have a friend who had one. Unfortunately his limited funds and short attention span meant that he rented more games than he actually bought, so my Sega experiences back in the day were mostly RPG-based with the occasional splash of Ecco the Dolphin and The Ooze. Years later it's nice to see that there's still plenty to explore and experience from the world of Sega.