I was trying to work on a similar-sounding problem at another school, and opened regedit but didn't figure out anything good to find for -- I tried POI but even that was getting too many hits, all irrelevant (I think).  So I was hoping for a further clue.  

Thanks for the update on the situation!

BTW, in that other case I ended up with a crazy workaround -- student computer #1 has the dvd drive but runs uneven, so we shared the drive and made it a MyNetworkPlaces item and desktop shortcut on student computer #2, and run VLC on #2!

Have a good break!  (And thanks for providing your Spring work schedule.)