I've seen plenty of books that were turned into awesome movies, so I can't see why the same can't be done with some video games. A lot of video games today are basically interactive movies, so all you need to do is take the interaction out of them. The only thing you would really need to change about the story is make it suitable for the big screen rather than having a story catered to working with gameplay.
Assassin's Creed would make a good movie. The story would probably have to be shorter than what we're given in the games, but I see no reason why it would work.
Gears of War could work too. Read the novels before anyone tries to argue against me, the Gears universe can make for a great movie.
Fallout could work if you just focused on the main story like what was given in Fallout 3.
Final Fantasy could easily work considering it's more a movie than a game. Hell, Final Fantasy DID get it's own movie.
Red Dead redemption can easily work.
Zelda can even work. The later games have been very much story focused than the earlier games have.
Mass Effect would be perfect for a TV series.
in short, they can work. Thing is they'd work better as a TV series like Mass Effect considering the length of some game stories. Either that or they'd have to cut the original stories to make them fit or make a new one altogether that would work for a movie.
Born to fight
Trained to kill
Ready to die
But never will
*ahem* I actually think videogame movies are doing better these days - in the same vein as the comic book movies (they range from mildly entertaining to effing fantastic). I mean, I really liked the Prince of Persia movie (never played it myself, but I watched my brother play it). I'm pretty optimistic they could make more videogame movies work, if they got the right studios for the jobs.
That said, I would love to see a Megaman film. <.< I never did play any of the games but I, ah, adored the cartoon.
I Witnessed And Survived The Great Valentines Crash of 2013!