You can use VLC to play a DVD on your MacBook Air via Remote Disc.
1. Launch VLC and go to "File" and choose "Open Disc".
2. Check the box next to "DVD".
3. Choose "File" in the tab menu in this window next to "Disc".
4. Check the "Treat as a pipe rather than as a file" box.
5. Click the "Browse" button and navigate to your Remote Disc DVD and press "Open" when you see the Video_TS and Audio_TS folders.
6. Click the blue "Open" button at the bottom of the window.
7. Enjoy your DVD!
There were some pauses (I was playing off an old G4 laptop) but it never lost sync.