Transcoding a DVD at high settings will be indistinguishable from the original, and will take half the space. For example, when I download shows from my TiVo, they're MPEG 2 files, similar to a DVD. I transcode to H264 into an MKV container. This format plays natively on my AppleTV. And at good settings, I lose nothing visible while getting a video file same size or smaller.I’m wondering if in my case, it just might be worth doing that.
I’m cool with the idea of ripping and converting stuff, but I’m less enthused about buying a computer to use as a media server. So maybe the long term project might be to make MKVs, which has the advantage of files that are playable on my system, that retain the extra commentary tracks and such, but don’t recompress the file into something even more lossy than DVD.
I almost feel like I want to see how the next few years of media charges go before deciding how to deal with this. If we’re in a majority streaming world in five years, then maybe building a legacy HTPC for all discs I own makes sense. In other words, maybe I should drop my half measure idea now until the future is more clear.
But, to rip ISO, I think you have to buy AnyDVD. For this to be free, MakeMKV is the way to go. Which has you either making a folder backup or extracting to MKV.
For your immediate problem of freeing up space in your apartment without losing favorite movies, you can try ripping a DVD or two with MakeMKV and see how it goes. If it's an OK solution for you, then rip your favorite couple dozen DVDs, and put them in storage. That solves the next six months concern, without spending much money or trying to boil the ocean to solve all video needs for the next five years.