DVD Decrypter is a great along with DVD Shrink and other programs to reduce the size down. For me, I just found that it was more hassle than it was worth in time vs space reduction. At least for the movies I fiddled around with (only 6 or 7 as a test), I wasn't getting big reductions in size since most were not "dual" wide screen/full screen. The audio track removals didn't seem to save much.
I loved getting all my CDs on one central system and MC 9.1 with MusicLobby works great. I had hoped to do the same for my DVDs too but even at 4 gigs a piece, I was looking at about 700 gigs of space (2 to 3 drives). I saw a Sony 400 DVD changer for about $350. The biggest "reasonably priced" hard drive I have seen is a 300 gig Maxstor drive (OEM) for about $270. But even then, I would need roughly 1.6 terabytes of drive space to equal one disc changer.
For me, that cost differential coupled with having to get it into a server tower, issues with noise, heat, etc, sort of made me decide to wait until +500 gig drives are the "norm". Who would have thought that a PC home user would ever need multi terabytes of drive space..haha.
Ahhh... I remember paying $700 for a 70 megabyte (yes meg!) drive in my new Mac SE (college days..some time ago!) and thinking that would be more than I would ever need.