My opinion, well i'm sure it matters little, i'm not going to tell you what i think, but yes XP Pro is probably a good fit. It networks easily, has all the features of the windows line, and allows for FAT32 and NTFS file partitions (including FAT32 on the install drive) I have been running XP Pro for about 3 years and i love it. If you like the feel and display of 2000, you can enable the classic style in XP Pro and set up links etc (i have a list as long as my arm of registry hacks for XP logon and display features) the same as in 2000. I have had the -well i'm gonna say pleasure- but i don't know if it was, of using windows 2000. The switch to XP may be hard at first, but once you switch you'll probably NEVER go back, i know when i tried, it just felt... wrong...
Also with the release of Vista (by the way, love the info card idea MS is really gaining my respect back) the cost of XP should drop considerably, similar to the drop win98/ME had after XP (but don't get me started on ME)
plain and simple: XP is the renewed face lift to Windows 2000/98 that Internet Explorer 7.0Beta was for the old IE. If you've seen the improvements, they aren't hard to learn and it takes a short while to like them and NEVER go back.