If you are able to reinstall the server 2003 software to get a clean machine, I would recommend doing this first. Next - run windows update to get the O/S bang up to date. Make sure all hardware device drivers are at the latest level for your machine.
Then download and install all the Visual C++ runtimes - both 2005 and 2008 are at SP1 if I recall correctly, and 2010 is available in both 32 bit and 64 bit versions, so choose the right one for your server O/S. Use the original admin account throughout.
That will ensure that you are running the latest runtimes before you install GSS. Leave out the A/V at this point. If it still fails then at least you know there is most likely something amiss with GSS.