Downloaded Amnesia via Steam - getting crashes

[dontkillmejustine]

I was gifted Amnesia: The Dark Descent through Steam, and when I try to open it, it crashes after I press "launch". I'm using a 2007 Windows Vista and I have more than enough space on my computer for this game, but it crashes no matter what I do. What am I doing wrong here? How can I fix this?

EDIT: It is a Dell PC.
EDIT2: The error message reads as follows: "Amnesia.exe caused an EXCEPTION_ACCESS_VIOLATION in module <UNKNOWN> at 001B:000000"... I have no idea what that means.