Hoping a Lurker has a solution.

[Tal]

They are 1.8ghz dell boxes. They came with windows XP SP2 installed on them. They give me an error when installing that

This system cannot install the selected windows product. For more information, please consult the windows compatibility guide at microsoft.com
(paraphrased)

If I could get an XP Professional license I would downgrade, the problem is, I don't have an XP Pro license to use to downgrade.

I have a vista machine on the network (the 3rd of the original 3) and it was a nightmare to get it to see things right, address right, and play nice with my GPO's. I would rather stay away from Vista after that

If I were more of a Hardware/network person, I'm sure that I could find a way to make Vista play nice, but at this point, it is me, a guy on the phone helping me, a Microsoft AD Server book, and lots and lots of googling.

Always nuke on a new OS install.