Windows XP Supported Upgrade Paths (Retail Versions Only)
http://support.microsoft.com/default.aspx?scid=kb;en-us;292607
Before upgrading any existing Windows installation, it would be prudent to
run the Upgrade Advisor for Windows XP. This tool will report what hardware
or software may be incompatible with Windows XP. If you follow the Upgrade
Advisor's recommendations, you should not have any problem upgrading to
Windows XP.
If you fail to utilize the Upgrade Advisor, you may run into incompatibility issues.
Just inserting the Windows XP Upgrade CD in the CD Drive and selecting
"upgrade" is not going to give you the desired result. You must "prepare and
plan" your computer before beginning the upgrade process.
Windows XP Upgrade Advisor
http://support.microsoft.com/default.aspx?scid=kb;en-us;307726
It is imperative that you have the latest BIOS update installed. Visit the support
website of the manufacturer of your computer or motherboard for instructions
on updating your computer's BIOS.
Accessing Motherboard BIOS
http://www.michaelstevenstech.com/bios_manufacturer.htm
HOW TO: Prepare to Upgrade Windows 98 or
Windows Millennium Edition to Windows XP
http://support.microsoft.com/default.aspx?scid=kb;EN-US;316639
Troubleshooting Windows XP Setup
http://www.kellys-korner-xp.com/xp_setup.htm
Also, physically disconnect all your peripheral hardware devices,
especially USB devices (not including your mouse, keyboard or
monitor). Uninstall any antivirus program, too!
Most importantly, it would be prudent to perform a backup of
any data files you have, just in case a problem should occur.
Important: When you are ready to upgrade to Windows XP,
make sure to select the default "Upgrade" option
during the initial setup phase. Do not select the
alternative "New Installation" option!
P.S. Be sure and visit the Windows Update site and download
all the critical updates after upgrading to Windows XP.