BB, yeahh, I would not even recommend 2007 for a P4.
I put 2010 in a Semprom 2.2 Ghz PC with Win 7. It actually ran OK, but only Outlook was opened. I can test it in 15 minutes (we have a meeting using that PC) using more stuff on it, but definetively the transparencies in the interface are not light. I wonder how it runs on Xp thought.