Cant Shutdown Windows Me

When I use Ctrl/Alt/Del and shutdown all runnig programs except Explorer & Systray my computer stalls and gets stuck in shutdown. I end up with a black screen with a square cursor blinking in the upper left corner ?
Here are the programs that I turn off = Nsched32-Atiptaxx-Lvcoms-Navapw32-Nprotect
Does anyone know which one of these could be causing the problem. I know I could try a process of elimination to find out! Its more fun seeing if someelse knows the answer :} Thank You