W2K3 role change

hi all,
I’ve inherited an existing network (well..sort of!) that has W2K3 Std Ed. Server running on Terminal Server level with 3rd party productivity applications installed and accessed by mix of XP Home & Pro boxes locally using RDP.
I intend to change the role of Server to local DC; with AD; User Management & Group Policies and as appropriate upgrade w/stations from XPHome to Pro for them to be part of the Domain.
Can you pls suggest best practice/considerations/things-to-note before I change Server role and elevate to DC.
Any response/s would be much appreciated.
cheers!
Eddie