Best Movie-Based-On-A-Video-Game:
Resident Evil - Apocalypse
with a nod of respect to 'Mortal Kombat'.
Worst - That insidiously-bad "Wing Commander"
As long as they don't screw up the plot, if it moves kill it, then it should at least break even. Looks like a renter to me and a possible addition to the DVD collection later on.
I'm a big fan of the video game. It's the only game that actually gave me the creeping willies. You just have such a constant barrage of stuff jumping out at you, and the creepifying atmospheric noises, that your adrenaline goes into over drive. Veddy cool...