Do you mean Word froze and closed? or the pc froze and closed?
If doc is read-only .... is it still open in Word?
suggestions to try:
or is it a read-only .doc in 'My Documents' ? (try rightclick | Properties and clear the 'read only' setting) or (rightclick | copy, and then paste, then change the 'read only' properties in the copy of file)
Did you close Word down, are there any messages on screen,
Have you reopened Word - Autorecovery should kick in and get last saved copy back and open it.