Just for future reference we do not condone copyright infringement.. We know are member's do not do this, but just in case..
Ok so when you copy your family DVDs your DVD player wont play the end.. Can you try this program? Its free and much better than Nero IMO.
http://www.mrbass.org/dvdshrink/dvdshrink32setup.zip
Also what type of DVD player do you have? And when using nero are you closing the session or leaving it open?