Move Primary Domain Controller from a Win2000 server to win2003

When an outside firm installed Win2003 on Two New Servers in our domain they were to make one of the new servers the primary domain controller. The primary domain controller was on a machine that could not be upgraded from Windows 2000 server to win 2003. They left the win2000 machine as the primary DC with DNS and DHCP on it. As expected the “old” machine is having problems and I learned when it was not working that no one can access anything after ashort while.
The old machine is now working but we need to move the DNS and DHCP to one of the Win2003 servers in the same domain. Can this be done and how?