Upgrade slowdown

[ComputerDragon79]

I just got two brand new computers I just got that already have XP pro on them and added them to a network domain run by a computer running Windows 2000 Advanced Server (the computers that were already on the network are running windows 2000. There only seems to be one problem, when domain users login, it takes a long time to "apply user settings" when people log with their domain user names. I can get around that by logging in locally as administrator, but is there a way I can fix that? Is there something in Windows 2000 Server settings I have to change because of the Windows XP computers being added? I tested it by upgrading one of the 2000 computers on the domain to XP and it does the same thing, and all the computers are fast and XP compatible so I don't think specs are the problem.