Windows 2000 Sever uprade from NT 4.0

Looking for recommendatation from this inherited mess.

Single NT 4.0 PDC network (no bdc)
roughly 25 users.

The rights on the PDC are extremely vulnerable. The users have ability to access the entire server.

My thoughts are to bring W2k on as member server. Move user data files from pdc to member server.

Take the pdc down and use DCPROMO to create a new domain.

Everything I read for upgrading address a network with a pdc and at least one bdc.

thoughts?