I may aswell smack down a few ressons why Mario is better. I am a fan of Sonic games as well.
Sonic can: run really fast, control the Chaos Emeralds and seems to be a pretty good fighter.
Mario can: Swim, Fly, Make fire in his hands, warp, Turn to stone, Grow twice his size, shrink, Wield the stars, cause earthquakes, Stop time, Save the stars, wake lightning, Fly at light speeds without dying (SMG) he is also super strong (As seen in SMG with the Bowser fights and SMS because he can drag arounda huge chain chomp which most likely weighs more than a truck) he is also a master fighter (SSB, SSBM, SSBB) and also a master in athletics. Oh and Mario dosn't need a fire flower to make fire just look at the Super Smash Bros series.
Im tired of hearing people say "Oh Sonic is better then Mario because he can take on robots and big monsters" Im pretty sure Mario can do that just aswell but Nintendo are sticking with there roots with Mario and keeping it fun, magical and wacky as it should be.
Mario can also hold up a full time job while saving the world and galaxy. What about Sonic?
I think iv'e summed up about everything. Iv'e played pretty much every game staring both characters all the way from the Golden Age of Gaming and based on how Mario has stood the test of time and Sonic just seems to be crumbling with every game I know what im going on about.