dvdshrink looks to be about as simple as it comes when you want to make a backup copy of your DVDs. It just takes your DVD and compresses/resizes it just small enough to fit on a DVD5 or common recordable DVD disk. The command line version dvdshrink is just a wrapper around command line programs. dvdshrink will output to the console the applications it's using to extract the contents of the DVD while it is running. It's a pretty interesting way to learn how the whole process works. Just look at the man page for each of the commands after the process is done.. well heck, you're gonna be there for a while waiting for it to get done so you might as well be looking at the man pages in another terminal while it's running.

xdvdshrink is just a GUI wrapper around dvdshrink for those of you whould would prefer a GUI. Using it can also familiarize you with the options for the script if you don't feel like sifting through the man page.