Many, many bugs...
Graphics: Sprites, not much else to say.
Style: Alright for a game. No plot or anything like that that usually comes with a Mario game.
Sound: Music was the Mario theme song remixed. Sound effect was appropriate.
Interactivity: AHHHH!!!! BUGSSSS!!!!!!!:
1) Can get stuck IN the objects. I don't understand how this happened, if you used the hittest function. You did use the hittest function, right?
2) In the level with the moving platforms, Mario does not move with them. Way to solve this: Write a simple script saying that when the platform moves and Mario is on it, then Mario moves with it.
3) It seems like Mario is floating when he is on an object. I dunno, how that happened, but only a minor bug.
4) Replay button does not work.
Fix those glitches and add more levels. Perhaps some enemies, like in the real Mario games?