Because W2k is a business edition you must use an upgrade edition of XP Pro
if you want to do an upgrade (not have to reinstall your apps). If you buy
an upgrade edition of XP Home you will have to do a clean install.
With XP Pro upgrade edition you insert the XP cd while W2k is running and
perform an upgrade. You will not have to reinstall your apps.
With XP Home you must boot the computer with the XP cd and perform a clean
install. In that case you will be asked for your Windows 2000 cd during
installation in order to verify that you are eligible for an upgrade
edition. You will have to reinstall your apps.
If you have to do a clean install, you can use the XP Files and Settings
Transfer Wizard to save your files and settings to intermediate storage for
reinstallation after XP is set up.
You should back up your files just in case something goes wrong no matter
how you proceed.