re: DVD ripping to external hard drive

MakeMKV to rip then handbrake to re-encode/transcode. Personally, I would use Handbrake settings that would be acceptable for watching on a Full sized TV, and then getting a Plex Pass and syncing any content to your kids tablets. It is a bit more work on the front end, and may require you to assemble a Plex server, but once it is set up it is really slick. A bit of warning, there seems to be an issue with iOS devices and syncing content. It is really slow on my wife's iPad/iPhone but I have no issue with any of my Android devices.