Restricting Guest Account options?

I'm trying to figure out how to remove the start menu (aka explorer) from the Guest account so they dont have access to anything, I've already made a few batch files on the desktop to shutoff, restart, and logoff. I put on the desktop only useful things like a shortcut to a shared file that they can work on and 1 program: Word. IE is also on there but has been limited in use as well. The reason I'm doing this is for maximum productivity, see if you cant do anything but access that 1 file... then thats all you can do, to me i think thats a good theory, plus they can't f*** up my computer by getting to anything, ive been searching the registry for the explorer settings and have already tried turning it off using msconfig but it affects both accounts which I dont want, anyone have any suggestions?