Solved it. For anyone who's curious I oppened the Utilities folder in Applications and launched Activity Monitor, then used this to progressively quit every running application. At some point I turned off something (I'm not sure what) which got us back to the log in window, from which I did a restart. The restarted machine then ejected the disk.
Does anybody know a better way to tell what applications are running? Call me a luddite, but I much prefer OS 9....... Bill Chesnutt
