That's a bummer. http://forums.cnet.com/7723-7582_102-524299/how-to-take-screen-captures-in-apple-s-dvd-player/ covers this issue and VLC to the rescue every time.
If the DVD has heavy copy protection then it can fail on VLC but you could research how to RIP the DVD so you can play it with VLC. But I will not discuss ripping.
I am trying to get a screenshot from a DVD of a movie I was in for use on my website (I am an actress). This particular DVD has some issues I have not come across with any other DVD I have. Normally I open the DVD files with VLC to take screenshots with keyboard shortcuts. I am on an iMac with OS X. Well, VLC will not open this DVD. Neither will MPEG Streamclip, my other workhorse. Only DVD Player will open it. As we all know Grab will not work with DVD player.
I have tried every trick and program that has been recommended in my search. Terminal, Screenshot Plus widget, I even downloaded SnapNDrag. EVERY program results in a blank screen. Is there any other program someone can recommend? Thanks