No access + can't remove

[nbelnap]

I did somethng wrong, I know not what.  QS is running in background,
but nothing I've tried gives me access.  Nor can I remove QS (to start
over), since I can't stop it:   doesn't appear on the Force Quit
list.  And OS X (Leopard) won't let me remove a running program.
Catch 58?  (The trouble began when I started messing with Preferences
via Command-, (which also does not work).
Help!