Have you tried installing Windows XP on Parallels? I did. No problem until I tried to install other stuff in Windows XP, like SP2. Actually, out of obligations, I had to install .NET and SQL Server, but in order to do that, you have to install SP2 first.
I got all kinds of errors, and some that merely said, “Data is invalid.” That is really helpful, thanks Microsoft. Anyway, after much frustration, I found that there are basically two things that can help this situation.
1. up the RAM – Parallels gives Windows XP 512 MB by default I upped this to 1024
2. install Windows XP with SP2 built in (don’t try to download SP2 later).
In order to do #2 you have to create your own bootable disk that has Windows XP and SP2 mixed in. Paul Thurrott’s SuperSite has a foolproof guide.