One reason that so many people give up with Windows Server 2003's RIS is that there are so many steps to a successful setup. Moreover some of the configuration tabs are hidden away. Paradoxically, once you realize that an installation is difficult it becomes easy, my explanation for this paradox is that you take more time and care when the project is challenging.
Logon to the Windows 2003 Server.
Install the RIS Service through the Add or Remove Programs, then reboot.
Go back to the Add or Remove Programs and complete part two of the install where you will be asked for the XP CD and a 2GB NTFS partition to install the 'vanilla' image.
To add more images,
create the perfect XP Client,
then run RiPrep on the client, I repeat, on the client not the RIS Server.
RiPrep will copy another, more complete image of this client to the RIS server.
A final point, to configure RIS on the server, you need to select the computer object in Active Directory User and Computers, properties,
then select the Remote Installation tab.
RIS servers, like DHCP, have to by Authorized before they start servicing clients.
My advice is to investigate Group Policies for RIS, decide on whether to allow the installer to choose setup options, or whether to make the setup silent with no screens and no choices.
PXE - Pre execution boot. A network card that boot and then request an IP address from a DHCP server