I have recently tried to copy a couple of disks in both nero and dvdshrink and get the following message: "Invalid DVD navigation structure". Any help would be appreciated. Thanks
Sounds like that particular movie your trying to backup contains a copy protection that DVD Shrink can't handle on its own. It's becoming very common now as Shrink is no longer updaded and has not been in a while. You will need additional software to break the copy protection. I recommend Slysoft AnyDVD as it is the best. However, it is not free. A good free substitute is DVD Fab Decrypter.
I have AnyDVD loaded, and have tried DVD Fab Decrypter, these films are quite old and are purly for backup.
Can you post the AnyDVD analysis on here? Just the short description of the copy protection it removed while the disc is inserted. Are you sure you have the latest version of AnyDVD running? "Invalid DVD navigation structure" is an error I get with Sony Arccoss copy protection, which AnyDVD takes care of without a problem now...