Here's an alternate suggestion: Walmart.

I realize that this will definitely not appeal to most people, but Walmart, who owns vudu, has a program where you can take your DVDs and blurays into the store. One at a time, they'll scan your movie to make sure it's the right one in their system, and then they'll give you access to the Ultraviolet copy of that movie, where you'll "own" it as part of your digital movie library.

Back when they first started this (something like 4-5 years ago now) I tried it out by taking them three of my most-watched movies. It was a slightly slow process, but the results were pretty good. I can watch those movies any time, and don't have to go to my DVD shelves and pop the disc in a player.

The downside is that if you're doing this with a lot of movies, it'll get expensive. They charge $2 a movie to go from DVD to SD stream or from bluray to HD stream. Or, you can pay $5 to go from DVD to HD stream. However, if you're planning on getting a NAS just for this purpose or buy gear to put a Plex server together, the costs might work out. A rough count of my DVDs tells me that I have about 180 movies, so that would cost me about $400, assuming I wanted to get the HD versions of some of those. I'd estimate that my NAS cost a total of about $950, though I use that for more than movies.

Fortunately, vudu has gotten much better about getting their app into more devices. It's on Roku, it has Chromecast support, it's even on Tivos (and I'm pretty sure there's an Apple TV app).

Again, I realize that this isn't for everyone, but it can be a nice alternative. You don't have to manage your library, you don't have to go through the ripping process, and you can still watch your content wherever you have internet access (no offline viewing, unfortunately). I just thought I'd mention it as a potential alternative.