Migration from NT to 2003

We have 3 NT servers 1 windows 2000 server no PDC all the above servers are sincronized not DHCP or DNS has been installed The reason for the many servers is when additional space was required another server was installed The plan is to consolodate the system and install windows 2003 on one of the servers, use that as a PDC with AD etc installed. The rest of the servers will stay NT and windows 2000 servers used as storage. A linux backup server was also installed. Please advice what or how the migration prosedure should take place with the minimum disruptions