Nothing that I've found for a Mac.  (Oh, have I 
tried and tried...)

You can't even use the built-in screenshot 
capability either.  It has to do with the way the 
DVD signal is overlaid on the video signal to the 
monitor.  Test it out & you'll see what I mean - 
take a screenshot of a frame from the DVD.  
(control-shift-3, not sure if it changed in OS X)  
Let the DVD advance a few seconds and then open 
the screenshot you took.  It displays the current 
frame, not the frame when you took the screenshot.

There are a few companies with good screenshot 
utilities.  I'm hoping they'll find a work-around 
for the DVD problem.

Sorry for the OT-ness.
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