Works in: 7 Stop--before you do one more thing with your PC, dig out the box it came in. Do you see a Windows 7 disc or a system-recovery disc? They're less common these days, so chances are it falls to you to create your own. And it's vital that you do, because if your system ever becomes unbootable, a recovery CD or DVD might be your only recourse.

Thankfully, Windows 7 makes the task exceedingly easy. Just pop in a blank, recordable CD or DVD (you'll need a burner, natch), click Start, type repair, and choose Create a System Repair Disc. Follow the instructions from there, remembering to label the disc when you're done.

If you ever run into trouble, boot your system with the repair disc. It includes a variety of recovery and diagnostic tools, and also lets you choose a System Restore point to help get your PC back to a previous, working state.

Make this disc now. If you wait until after you encounter a problem, it's too late.