After installing Windows 2000 on the new box and applying SP4 and all
relevant hotfixes, point the new server to the old one for DNS resolution (I
assume you're running DNS on your existing DC). Use dcpromo to add the
second machine as an additional domain controller and then transfer the
Operations Master (FSMO) roles to the new box.
Make sure your workstations and servers remain pointing to a valid DNS
server for your AD domain at all times.
Use AD-integrated DNS to simplify things. When the new box is online,
install the DNS Server component (after making the switch to AD-integrated
DNS). The DNS zones and configuration should replicate to the new box
through Active Directory. When you're happy with that, point the new server
to itself for DNS resolution.
Next, transfer the FSMO roles to the new box.
It sounds to me like you only have one domain controller. This is very
dangerous, as if you lose your last domain controller, you'll be in serious
trouble. It may be worth keeping the old server running as an additional
domain controller if this is the case.
If you still want to remove the old machine, ensure that no workstations or
servers are reliant on it for DNS, DHCP or WINS, etc. You can then use
dcpromo.exe to remove the server from the domain.
Oli
