Here's the short of it: I am completely unable to boot into Windows 7 either normally, or through safe mode. Running a boot disc and trying to reinstall doesn't work either. This just happened suddenly after a normal reboot.
When trying to enter Windows 7 normally:
It gets to the splash screen with the animating windows logo and just sits there. The logo continues to animate so I know it's not frozen, but it won't go any further no matter how long I wait.
When trying to enter Windows 7 Safe Mode:
It gets to the screen where it tells me it's loading drivers. It gets as far as "CLASSPNP.sys" with "Reading Windows files" at the top of the screen and then gets stuck. Doesn't progress no matter how long I wait.
When trying to reinstall Windows 7 from boot disk:
I specify that I want to being installation and it tells me it's starting Windows installation and then sits there.
I have quite a bit of experience with computer but I am at a total loss as what could be wrong here.
Any help would be greatly appreciated.
Sorry to trouble you all - I figured out what was happening. My Velociraptor hard drive has decided to pass out on me and as a result Windows was misbehaving.
Maybe it is because of the orientation of the drive in my tower (it sits on its side instead of lying flat), but I have had quite a bit of trouble with these Velociraptor drives. For anyone considering buying one, I would seriously consider a good SSD before I bought a Velociraptor.