How To Perform a New Installation of Windows XP - Part 1 of 3

By Tim Fisher, About.com Guide

To begin the Windows XP installation process, you will need to boot from the Windows XP CD.

1. Watch for a Press any key to boot from CD... message similar to the one shown in the screenshot above.
   
   
2. Press a key to force the computer to boot from the Windows CD. If you do not press a key, your PC will attempt to boot to the next device in the boot order, which is probably your hard drive. Since your hard drive has no operating system on it, the boot process will fail.