If you have a "shut down" wav check it. A corrupt file will cause a system to hang during shutdown. If you have disabled such sounds then no need to check it. Internet Explorer had some problems causing such a symptom. One word of note. I downloaded the "fix" for the IE shutdown problem from the Windows Update site, and then I had the problem lol. Mine eventually cleared up although I had to hit <enter> to get a complete shutdown for while. Before shut down check your program runnings list (ctrl-alt-delete). End task any you suspect and wait for them to halt and then try shutting down.