Domain, forest and migration

I've a Windows 2003 domain and another Windows 2000 domain.
I need to put the Win2000 domain in the same forest o Win2003, but for
this i must launch DCPROMO, remove activeDirectory from Win2000 (this will
delete al AD accounts...) then relaunch DCPROMO and add the Win2000 to
2003 Forest.
I can do it without remove the Win2000 Domain ???

Thanks,