I've tried most of the ones listed here. DVD Decriptor and DVD Fab are the best at getting by the copy protection. In general the hardest disks to copy have Sony's ARrCoSS protection, then it comes to Disney. Disney usually has some game on the disk that actually messes with several of the rippers. DVD Fab can usually crack both. I usually have it copy the whole disk 1:1 to the hard drive then use DVDShrink to make it fit down to a 4.9GB disk. I usually set DVDShrink to do the highest compression on the extras, titles and everything but the main movie then do the automatic compression level on the movie itself. This frees up more room for the movie so it does minimal compression.
Some disks can copy 1:1 on a standard disk with room to spare.
I have yet to successfully backup Shrek (1). I've gotten the movie, but not extras, or the whole disk without sound, etc.
Just remember, on discussions like this everyone must remember to keep it legal. I make backups because I have a 2-1/2 year old who likes to press buttons and plays with whatever comes out (DVD's, VHS, CD's, etc).