Overview
Do you need to record a dvd clip for commentary? Chances are you will use Handbrake since it is free, open source, and actively developed.
Installation
Since I am using macOS, I like to install HandBrake using brew.
brew install handbrake
DVD Recording
Now that HandBrake is installed, insert your dvd and start recording! However, you will get a scrambled mess 🙁 because the dvd is encrypted.
Scrambled DVD recording.
Not a problem. Close HandBrake and install libdvdcss library with brew.
brew install libdvdcss
Open Handbrake and your recording will no longer be scrambled.