The current network configuration is as follows.
Server 1: Windows Server 2003 R2 (Server in question to reformat) Primary Domain Controller + VPN + WSUS + DHCP + DNS
Server 2: Windows Server 2003 R2, Exchange 2003, DFS, SVN, Secondary DC
Server 3: Windows Server 2003 R2, Backup DC, DFS
Server 4: Windows Server 2003 R2, Antivirus Server, Remote Access Server.
Server 5: Windows Server 2008, Development Server. (not really important in this question)
The back story is that Server 1 (the Primary DC and Global Catalog server) was originally just a WSUS and ACT (Act is like Sales Force) server. Basically a non essential system. We had a disaster and the only option was to upgrade that server to become the Primary DC and GC Server. I do like the hardware on the machine and our current configuration, but feel it should be setup properly if we are going to rely on it.
I would like to know step by step what actions must be taken to reformat the machine.
Can I retain the same computer name? Do I have to demote the server and promote the backup DC (Server 3) then reformat then promote Server 1 back to Primary DC and GC? I am not worried about the services on the machine as those will be easy to move to another server. It is mainly the Domain Controller function that I am curious about the proper steps for this sort of project.
Anything I am missing here please let me know and I will update.