XP is not a server OS, it\'s a workstation OS. 2000 Server and Advanced Server and Datacenter Server are MS Server OS\'s.
And nobody, and the Emperor means nobody, is going to host their domain on a Microsoft OS. It\'s not smart no matter what u think of them. UNIX boxes can go for months without having to be altered or rebooted. A bad hair day can set off Windows machine to a fatal error requiring downtime and loss of data, which means a lengthy restore from tape usually.