At the top of the video game adaptation genre.

Rating: 7/10 (29 June 2010)

"Congratulations, Rose. You're here. You did it. Your reward is the truth."
It's not often that video game movies succeed in being entertaining while also keeping in the spirit of what made that particular game successful in the first place, but Silent Hill pulls it off as well as any other attempt that I've seen. It works not only as a game adaptation, but as a horror movie, as well.
I remember seeing it in the theater with a rather large group of friends, and we all (and most of the audience) were pretty freaked out by it. It's not nearly as frightening after repeated viewings, but the spooky atmosphere and perverse creatures remain effective. It certainly helps to know about the mythology of the town and the characters, but not exactly necessary. You'll still get most of what the movie is about.
The pacing is deliberately slow at times, because like the games, the focus is on building almost unbearable atmospheric tension (aided by fantastic music lifted directly from the games). This goes hand in hand with the surreal, terrifying sets and the oppressive darkness that falls upon the town when the nightmare creatures appear. You may find yourself cringing every time you hear the sirens (like I did), wary of what kind of horror Rose (played by the gorgeous Radha Mitchell) is about to have to face next.
On the negative side, the script is incredibly clunky, at times. Stilted and obvious dialogue occasionally draws the viewer out of the movie, and a bit more subtlety would also have been welcome. The villains really are almost comically evil. It's hard to imagine that even they believe that what they're doing isn't horrible.
Silent Hill is a gory, intense, nightmare of a movie. Just as a film adaptation of this property should be. It's proof that good results can occur when a video game is treated as more than just an easy cash-grab and is adapted competently.