Prior to asking me to do tech support, my brother
installed Windows 2000 server on his computer. He isn't
using it as a server and Windows XP would work better for
what he is doing. A friend told me that installing XP
over win 2000 server would wipe out all the software-
related registry entries. Can someone tell me how
preserve the entries when I can convert to XP?

Upgrade W2k Server to XP is the unsupported path.