Well ya it was supposed to be based off a video game so the plot would have been kinda weak anyway. The real problem is that Uwe Boll got his hands on it - so befitting his track record it had nothing to do with the game. He really should be banned from making video game movies - or movies in general. I would rather be forced to watch an M Night Shyamalan movie.
So would I. Then again, Shyamalan is... oh, I don't know, a respectable filmmaker who has directed several great films over his career, despite the recent "Lady in the Water" and "The Happening."
But this is not the discussion at hand.
House of the Dead was an arcade shooter. It was never designed around a strong plot, and should have never been translated into film, especially not by the hands of Dr. Boll. There iss essentially no similarity between the games and the film, aside from zombies.