network Lap

I am setting up a test network and I would like to know the best method. Could I create a child Domain as a test network? I want this to be on the network so I can move files back and forth.
I have one Windows 2000 client and one Server for this test network, I want to be able to create profiles,scripts and test them. Also could I run Exchange on this server one the network with our company Exchange server on the same network