Thanks to a stupid law, every DVD player (that includes the one in your computer) is sold being able to play only discs with the same region as the country it was sold in. That includes Macs too, sort of. On a new Mac, the DVD drive is automatically locked to the region code of the first DVD it is used with. From then on, this can only be changed four more times.
You pretty much have two choices — either find the region code that you'll be using the most and set it to that one (since the four times are going to be used up sooner or later) — or "flash" your drive to the region free, which goes with the risk of destroying the drive. Below are tips to play different region DVD on Mac (EL Capitan, Yosemite and Mavericks included).
The Easiest Way to Burn Any Video to DVD
If you have a number of videos on hand and would like to burn them into DVD for storage or playback on DVD player, iSkysoft DVD Creator for Mac (or iSkysoft DVD Creator for Windows) is the highly recommended DVD burning software. With it, you are able to burn any videos in any format into DVD in high quality.
You can also edit the videos and add a unique menu to your DVD to make it special. Background music can be added to fit your theme. Whether the videos are shot with your iPhone, iPad or captured with your camcorder or camera, you can turn them into DVD easily. Just take a trial.
Simple Steps to Play Different Region DVDs on Mac OS X (EL Capitan included)
Download and install VLC and open it, then select File > Open Disc.
Click on the Disc tab -> click on DVD -> select the device -> click OK (usually this is selected by default). The DVD will now play, and your region code will remain intact.