Hi
Decrypters are often the most important part of a arsenal for backing up DVD's & Blu-ray's.

FREE!
http://www.dvdfab.cn/passkey-lite.htm
DVDFab have others that are more comprehensive, at a cost.
There others out there.
http://www.dvddecrypter.org.uk/
http://www.dvd43.com/

Simply "Magic" with no need for additional software.
Two I recommend:
From the same stable.
http://www.magicdvdripper.com/
http://www.bluerayripper.com/
These are not free.
But have never let me down.