1. When you start dvdxcopy you should have 3 little windows. One for disc 1, one for ommited features, and one for disc 2. By default it usualy ommits all the extra features. So in disc one and two you should have TitleSet 1(the main movie) and VideoManager. You can save some space by choosing the "start with movie abandon menu" option(or somthing like that) If you have this option selected and all the special features ommited and it is still too big you will need to use 2 discs, in that case you might as well keep all the special features.
2. I just bought 50 double dvd cases off ebay. Good prices there.
This is what I bought. Works out to be 65 cents a case after you tack on the shipping cost. I thought 12.50 was a little much for shipping but 50 case is actually pretty heavy.
3. There isn't really a standard. Movies are encoded differently, then you have special features and such. Every movie is different.