Pinkston32 discovered about 20 missing or corrupt drivers messing up his system. He asked the Answer Line forum what to do.
Start by restoring your system to a point before the problems began. Select Start, All Programs, Accessories, System Tools, System Restore and follow the prompts.
If that works, sigh with relief, but consider the fact that you may have fixed only a symptom. Scan your hard drive with SuperAntiSpyware or Malwarebytes (or both) to make sure its not infected. You might also want to run CCleaner, which cleans up a number of other, not intentionally malicious, problems.
But what if System Restore doesn't do the trick? In that case:
1) Go to Device Manager: Select Start, Run, type devmgmt.msc, and press ENTER.
2) Uninstall all of the corrupted drivers: Right-click each one and select Uninstall.
Windows will find and reinstall whatever drivers it can. They won't necessarily be the most up-to-date drivers, and some will be generic ones that can only run your hardware in limited ways. But your computer will be working and you'll be able to install the other drivers from CDs, manufacturer Web sites, and so on.
Thanks to all the folks at the PC World forum who contributed to this answer on the original thread.