I downloaded the demo for Call of Duty 4 earlier and went to install it. After configuring itself etc, it told me the Windows Installer needed to reboot before continuing. I let it reboot, and now the computer won't boot! It goes through the initial BIOS screen and when the screen goes black, just before the Windows logo is supposed to come up... it stays black. I have no HDD activity light either. I've chucked in the XP disc to try and repair, and after it's loaded the initial set of drivers and says "Setup is starting Windows", nothing happens. What the hell? How can a demo do that? Also, where can I go from here? It won't boot into Safe Mode either!
That's definitely not supposed to happen. Maybe you should try a Linux-distro-on-a-Flash-Drive and boot into that.
the demo had nothing to do with that try getting in the repair console and running a chkdsk /r, it usually helps a lot for windows that can't boot
Yep, I agree sounds like a horrible coincidence. You just happened to have problems just after installing a demo. Any chance you can try booting from something else (cd or usb stick) sound like the hard drives had it to me.