My experience thus far:
I have burned several previously decrypted iso images using K3b, NeroLinux and Gnomebaker, and the programs work 1 time then require a reboot before being able to burn another. I tried turning off auto eject and a few other things but so far no luck. I have started using the command line, which has worked every time so far. growisofs -dvd-compat -Z /dev/hdc=filename.iso. I am happy using the command line and hate needing to reboot, so burring the image to the dvd using the command line is fine with me.
Most recently I used k9copy to shrink a dvd9 to dvd5 iso, complete with menus and it worked OK after using
growisofs -dvd-compat -Z /dev/hdc=filename.iso I have yet to try ripping a previously purchased dvd.
Other than dvdshrink and dvd decrytper, I have yet to find anything that works well in wine. I tried several versions of Slysoft AnyDvd and a few other programs to handle the dvd decryption. I have been unable to find any really good methods in linux to make a backup of a recently purchased dvd, but still looking.