If the damage is one I know of, it's not possible for me to write a step by step for this one.
Did you try an USB keyboard so you're sure it's Windows and not the hardware?
I have Windows Vista (32 bit) installed on a Dell XPS 1530. When I attempt to login to Windows the keyboard is completely non responsive. It does work when I press F2 to go into setup mode though. How do I fix it? I really don't want to wipe everything and reinstall Windows. I've already tried restoring to an earlier date from the Windows disk, but it says that there isn't a suitable backup.