4. Download Updates

At some point your PC will tell you there are Windows Vista updates available. If you haven't already, feel free to grab them. You may have an icon in the system tray at the lower right, or you can select Windows Update from the main Vista menu at the lower left (choose All Programs to find it).

Depending on which version of Vista has been installed on your computer and when, you could have quite a few updates—big updates—to download. Let this process run its course. Walk away. Eat some leftovers, go out for a mocha latte, watch an Adam Sandler movie. It's going to take a while, and the Sandler movie will seem to last forever.

When the downloads are done, run Windows Update again. Updates tend to beget updates. Three times should be sufficient. By now you've got a truly pristine system.