>>>>I have never found a movie that DVD Decryptor can't rip!<<<<
So far, there are only three or four that have been discovered. None of these three or four appear to be Region 1 (so far!) and all of these are a newer variation of Sony's ArCCos copy protection scheme, but they changed the structure again, and just as LighteningK was about to release a newer version to deal with these newer discs, he received the "cease and desist" order (which did NOT come from Sony).
You can find information on these new discs by doing a search on "Closer" and "Region 2," I know that one has been discussed a lot.
Also, it is possible to create your own PSL file (customized) for these discs. The PSL file basically tells DVDDecrypter exactly where the "bad sectors" are that Sony / Columbia / Tristar has deliberately placed on these latest discs. Then, one must add that to DVDecrypter's file folder, as some have successfully done. However, most people do not yet understand how to create their own PSL file. I believe there are now working PSL files for all of these "new problem discs" which have been posted around the Internet.