Try DVD-Rebuilder which can use free to download mpeg-2 encoders other than CCE; although it works best with CCE Maybe you thought that methods using CCE require a more in-depth knowlege of DVD structure and other utilities but with DVD-Rebuilder it's a really simple process on the part of the user and does a fantastic job. The only limitation at the moment is that you can't back-up titles with seamless branching* and multi-angles, however that is in the pipeline from what I hear.
There are test results using different packages for shrinking DVDs online somewhere - I can't remember the site sorry - but the versions of software used on the tests are long out-of-date so aren't that useful.
Also remember that removing objects from a DVD doesn't always result in a playable copy because the navigation instructions on the DVD may depend on these objects being present or may indeed have navigation instructions themselves. Undiscovered bugs in software or utilities can complicate matters. Sometimes it works, but with titles and navigation programming becoming more complex you're bound to run into problems before long.
*Seamless branching is a technique used, for example, to store different versions of a movie that seamlessly play-back an alternative version of a scene without having to store the whole movie several times.