This is quite easy.
QuickTime player can play DVD but not Blu-ray, so ...
... can play your BDs with your DVD player, you can try QuickTime player ... 'd better [convert Blu-ray to a QuickTime format][1].
[1]: http://www.brorsoft.com ... -to/transfer-blu-ray-to-quicktime-on-mac.html
... -ray ready. Try using Quicktime to open the discs instead ... you need additional codecs because Quicktime might not be able ... or drive over Quicktime and the content will be played automatically.
Install the update of Quick-Time from the Apple Website... Your problem will be Solved...