There are a wide variety of rippers. I THINK FREEMAKE can rip dvd's. I know it can convert between the various formats. Obviously, ripping high definition, high quality results in larger file size. Some folks want the best quality. Others want a more reasonable file size. Also, it might depend on whether you want to watch only on a tablet or use hdmi (or screen mirror) to show it on a large screen tv.
Whoops, I see the topic may be off limits. I believe there are jurisdictions where you may copy your dvd. And actually, I have ripped dvd's that I have created from Travel pictures that I did burn to dvd using Magix software. Then suddenly found that I wanted them on my BB Playbook and my Z10 and now have moved some of them to the Tab S.