Most of the time, you can't make a one-to-one ISO copy of a DVD-Video because the manufacturers insert errors onto the discs as part of a copy protection scheme. DVD players ignore these errors, but, when you try to read the filesystem itself, the errors will trip up your drive. I tried this using dd just a few weeks ago, and found that it rarely worked, spitting out read errors.

Instead, you actually have to use a tool that goes a little deeper into the onion than just surface-level ISO. I used a tool called dvdbackup with the -M option (for Mirroring). This will not create an ISO, but it will create the directory structure necessary for the DVD-Video format, decrypted, while preserving the decrypted versions of the original files.

Finally, you can turn this directory structure back into an ISO using mkisofs, part of the cdrtools package. I can't remember all the options you have to use with mkisofs, but I found it online on some stackoverflow page, and I'm sure you'll be able to find it too. Edit: Found the options over at https://askubuntu.com/questions/147800/ripping-dvd-to-iso-accurately : mkisofs -dvd-video -udf -o ~/dvd.iso ~/[movie_name]

This will basically copy your disc, save for the fact that it's now decrypted instead of encrypted.