Snapz Pro http://versiontracker.com/dyn/moreinfo/macosx/11530
command+shift+4 to grab screenshot
screenshots are disabled during dvd playback or pause.
works via timbuktu from a remote computer, however.
Pull up a command-line terminal and use screencapture.
command+shift+4 works if you use VLC for playback:
http://www.videolan.org/vlc/
