As a general rule, DVDShrink fails to decrypt and rip the newer movies to the hard drive rather than waiting till you try to burn them to disks.
Jethro’s suggestion of DVDFab HD Decrypter is a good one though, as it is just about the only effective decryption/ripping program left that is free to use. http://www.dvdfab.com/free.htm
But I’m not sure decryption is the main problem here.
Try ripping the movie with this program, then start Shrink and hit Open Files…navigate to the movie files you just put on the hard drive and see if they need to be compressed to fit a blank dvd. Then try burning to a disk in your usual way.
If this fails, you might want to check the DMA status of your drive.
It might help to know the burner you are using and the blank dvd mid codes. Load a blank dvd into the drive first. You can use a free program called Nero Info Tool to find the burner make and model (top of the opening window) and click on the Disc tab to see the Manufacturer ID code of the disks.
If the DMA status is good, you may simply be using poor quality disks.