Removing Dell's default windows theme

Hi,

I just recieved a few Dell systems that I ordered and because of lack of time did not do a complete rebuild of them for the image. It was going fairly well until I noticed that the system was ignoring the group policy settings for the desktop theme and start menu. I, as I'm sure many admins do, set it, via group policy, to look like win2k. I have done it before with winxp clean installed and it always worked. But on these Dells it is simply ignoring the group policy for the desktop settings. Does anyone know how I can ditch the Dell customizations? I am rather pressed for time and would not wish to do a clean install and reconfigure everything again.

Thanks,

J. Paulsen