How big can be the differences between Windows 2000 and XP?
Basically the defragmentation API wich Defraggler uses is the same(or backward compatible)
Why to drop this very robust OS wich is w2k?
I am sure this can be done with a minimum efort if The Team really want this.
There are still others programs to defrag a drive wich don't force you to change your OS to use the newest version.
Sounds like MirkoSloft has inspired most of the programmers to force upgrading, why not to Vista or 7.
Hope this don't apply HERE, so please, TEAM, don't drop w2k, it is still used by 'some guys' and does well his job.