Odd REALLY dark and inverted colors

[zjod95]

So every time I run Amnesia, it ALWAYS turns out to be really dark. And by that I mean if I ever light a torch or lift my lantern, no light comes out. Also, everything that is normally dark turns to either pure black or dark purple, and anything lighter is green or white. This applies to the main menu and the game play. But in the options menu and loading screen, everything is fine.

What's wrong with my game? How do I fix it?

[zjod95]

To further elaborate on this, you know how you can see stuff in the beginning? Well, I can't even see the Old Archives door because it is black.

If it makes any difference, my comp is a HP dv6000, Vista, 2 GB RAM, 1.8 GHz, NVIDIA GeForce Go 6150.