Automating the installation of Windows XP and placing the Windows XP CD files to the server are a little different.
You can copy the CD files (primarily the i386 directory) from the CD and place it on a share on the server. You can then copy the SP2 exe file to the same location. This would allow the XP installation files (i386) and SP2 available to anyone on the network.
If you want to setup a way to easily reimage new machiens, there are a few ways to do it. Windows Server 2003 includes Remote Installation Service (RIS). This would allow you to setup XP images for deployment. Another way you can do this is to setup network boot disks that would allow the computers to be booted into a DOS-like mode and be able to access the network. From there, you can navigate to the share that contains the XP installation files and run the appropriate files (I forgot which one). Another way is to setup XP images on CDs with SysPrep. This would allow preconfiuged images to be easily installed, without you having to sit next to the computers and clicking Next and OK's.
I can't provide much detailed information on how to do these or what's involved in the procedures since I haven't worked much with these, but this should give you an idea on what path to take. The RIS route may be easiest since you would be able to easily PXE boot and go from there.
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