norton is a pig. it hogs so much of your system, and is very difficult to truly shutdown. it likes to restart its self. best bet is to uninstall norton completely and get something like AVG, or Avast, combine those with spybot, or adaware, and you will be just as, if not better, protected than with norton. IMO
and yes, with fsautostart, if you mess up and disable a process you shouldnt have, just restart your comp and all is well.