DVDRebuilder... It has a one-click mode. After you set your encoder paths and other preferences it is very easy...
I agree, DVD-RB is a simple to use as other similar one click applications. Furthermore, one should not overlook the advanced features of the pro version in terms of backup options.
For a very simple to use 1Click program that still retains a quality film after shrinking. I would recommend 1Click DVD Copy (lgsoftwareinnovations.com) it really is a one click program. You will need to have software like anyDVD or DVD43Free or any other software blocking software running to back up commercial DVD's. I purchased 1Click and love it its $59 and includes lifetime updates. I believe anyDVD is $39 while DVD43Free on the other hand is free but is not updated as frequently and is known to cause problems on some peoples PC's. 1Click DVD Copy allows you to copy up to three movies any way you want before you are required to purchase the software. And anyDVD has a 21 day trial.