Upgrade NT 4.0 to Windows 2000 OR ??????

I have 15 NT 4.0 Servers and about 100 Windows 95 clients. We have decided to move to Windows 2000. Should I upgrade the PDC and then add newly installed Win2K Domain Controllers and then turn around and reinstall my old PDC or should I just upgrade my PDC and subsequently upgrade all my servers? I am in desperate need of documentation of the best path to take to accomplish this goal. Any and all help or info would be much appreciated.

Thank You in advance.