If you can afford it, try to find a refurbished 2005 Windows Media Center machine (if you don't have one already) if you are interested in playback on TV, they are perfect for massive DVD libraries since there is a plugin for this now (free), and it supports some of the commercial DVD changers as well now (just a select few, but expensive). MCE is easy to navigate, even for kids.
If you just want to play them back on the computer screen, then it should be pretty cheap to do.
I use DVD Shrink as well, since DVD Decryptor has been shut down. Works great! I strip just the movie with the right sound track (AC Dolby 5.1), which keeps the size down. Make sure you disable compression if you care for quality (kids probably don't tho).