The copy dvd function that you used the first time would have worked if the movie was small enought to fit, but since most are not, you need to compress the dual layer disk to fit a single layer disk (using nero recode). Go to nero start smart, select dvd at the top, go to copy and backup, then "copy entire dvd-video". That will open nero recode, the program you want (you might see some similarities to shrink as both programs were written by the same person, though nero recode has been updated more). Try that and tell what problems you have/post the log.