You would never want to do this in the corporate world, but with a test VMWare instance, it makes sense. I am already logging into the host machine, and so, why should I log into the VMWare machine again each time that I boot it.
So. I used the link below to have the machine automatically login when it boots:
How to turn on automatic logon in Windows XP
It did work for Windows Server 2003. I used the registry method, but I opened the dialog with the Start > Run … control userpasswords2, and it looked like it would have worked as well.
Guys take Logonexpert autologon tool that encrypts password and perform logon to domain.