You can set Dvd Decrypter to ignore read errors.
Thoroughly clean the disc before starting and then use Decrypter to extract in file mode. Have Decrypter set for 20 software read retries and to ignore read errors. Whilst this may take a while, if the disc is clean, you'll probably be surprised at how few read errors will actually occur.
After ripping, run Dvd Shrink on the extracted files to compress, if required.