the_heretic
Since I do not have direct experience with servers, I did some searching on
Windows Server 2003 and only came up with one thread in the forums that indicated WCG was running on this platform. In the thread (which can be seen at
http://www.worldcommunitygrid.org/forums/wcg/viewthread?thread=691), the member is addressing a problem with the length of time that a work unit running on Windows Server 2003. I would deduce from this that the WCG software should run on Windows Server 2003. As for the "Agent Paused" issue, much has been written about this in the forums and much of this has been digested in the Help facility available through the button at the on the selection bar above. Using the Help facility, you will be directed to this page
http://www.worldcommunitygrid.org/cause.html which discusses possible causes. I would pay particular attention to the system requirements as it would appear that you are running on a fairly old system.