I guess the main problem is that those movies are advertised as movie adaptions of video games, whilst most of them do have that much in common with the actual game. I find it pretty cheap to draw audience that way (who remembers the Final Fake-asy - Spirits Within? - I know it's not from boll, just the prime example of drawing-techniques)
That point aside, if I let the titles of the movies vanish and just value what I actually see on screen, I seriously think I can spend my time better by doing something else. I just do not enjoy movies that are bad paced, no matter how many well known actors play in it.
It's a shame when a movie bores me that much that I fall asleep (dungeon siege, per se).
I find it sad when I think about all the things that could have (easily) been improved to make the movies just plain better overall.