DVD Screen Capture Workaround
Why can't you do a screen capture (Command Key-Shift-4) when running the DVD Player application on your Mac ? Presumably because of copyright issues. However, surprise surprise, this technical barrier is not solid. Macfixit gives the workaround: type "screencapture-c" in the Terminal.
- - -Udate: Macfixit notes some other ways to override the restrictions.