Found it!  Seems you must switch the internal wireless receiver ON or
windows goes looking for it regularly (and stalls the computer).  If you
disable the wireless connection in software, all is fine, but if you leave
it enabled and just use the tiny switch on the front/left corner to switch
it off, this will happen.  I'm 99% sure it wasn't always this way, but now
since I've put that dreadful pain-in-the-butt ZoneAlarm Security Suite on
it, things may have changed.

Randy