Scytheress
I'm guessing you're also using Vista. Oddly, starting the same night, my boyfriend's computer began having the same issue but we resolved it through another method. If what I said above doesn't work I can walk you through the longer process to fix the KSoD (black screen of death, exclusive to Vista).
My desktop with Windows XP professional did this
neutral . You couldn't do ANYTHING WITH IT! I had to reinstall XP.
I'd say reformatting is usually a last resort, but OP, do you have your operating system disks? I'd recommend inserting them now, hitting F12 (I think...) will get you the boot menu, you want to boot it from the CD/DVD drive, and it usually guides you how to completely reinstall your operating system, since that's all your really can do , at least with my experience with this error.