You need to find out which of 99 titles is actually the movie. I found the next paragraph on macworld.com that explains how to do it.
Just insert the DVD and let Apple’s DVD Player application play it. Skip through the previews, commercials, and whatever else crops up before you can watch the movie. When the main feature finally begins playing, push your cursor to the top of the display to reveal the menu bar. From that menu bar choose Go -> Title. Scan down the long list of titles and you’ll see a check next to one of the titles. This is the title number of the real main feature. Make a note of it.
You can now return to HandBrake and instruct it to rip this title as the main feature. All should now be well.
When you start Handbrake click cancel (don't select a source).
Click "File", then "Open Source (Title Specific)..., then the box pops up that normally does looking for you to select the source. Select "The Dictator" as you would normally.
Now another window pops up asking you which title you are looking for. For my copy of "The Dictator", it looks like it's #59. Mine is running at the moment.
The above report about opening title 59 works fine as long as you do it as soon as you start handbrake. Fooling around with different methods leaves Handbrake in a state where it cannot open any title. Restarting handbrake and following the procedure worked fine.