Best way to downgrade from XP to Win2000?

[Byron172]

Does anyone have any suggestions as to the best way to downgrade an operating system from XP to Win 2000. I'm currently helping out my Grandma who has an old computer that can't cope with XP, however W2k should work just fine. I have installation disk for Win2000 and XP.........
Cheers,
B

[Kwitko]

I think a clean install is the only way.

[Thrax]

A clean install <b>is</b> the only way.

[Byron172]

I've wiped the hard drive after backing up her files, and now when I insert the Windows 2000 cd it says it connot start set up as there is no "swap" file. Any suggestions?
PS - When I put in the XP cd set up starts as normal, do I maybe need to create a boot disk to install W2K?