You may be able to play the disc by opening it as a Video_TS folder instead of a DVD, or by changing the method used by libdvdccss to decrypt DVDs (go to Preferences->All->Input/Codecs->Access Modules->DVD without menus->Method used by libdvdcss for decryption). However, the DVD drives on most new Macs have region lockout on the hardware level, so VLC will not necessarily be able to play discs from multiple regions. Many people try to use VLC to play DVDs from regions their drive is not set to. Why won't VLC play DVDs from a region other than what my drive is set to? On other RPC2 drives that do allow raw access, it might take VLC a long time to crack the key. You will need to flash your drives firmware, but sometimes there is no alternate firmware available for your drive).
So with those drives it is impossible to circumvent the region protection. VLC uses libdvdcss and it needs raw access to the DVD drive to crack the encryption key. Some of these drives don't allow raw access to the drive untill the drive firmware has done a regioncheck. The problem is that a lot of newer drives are RPC2 drives these days. Testing it is usually the quickest way to find out. VLC works by ignoring any reference to region coding Pls post link to someone who did this on current or recent Macs. It's been done before by many people with great success.