Here's how to get VLC media player to play a DVD automatically on insertion in Mac OS X. First, create and save this AppleScript:
tell application "VLC"
OpenURL "dvdnav:///dev/rdisk1"
play
end tell
Next, open System Preferences, and go to the CDs & DVDs tab. For the When you insert a video DVD option, in the drop down menu select Run Script, and then select the AppleScript you just saved. That's it!
Mac OS X Hints
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