If they are movies then they are subject to copyright and have copy protection on them and this will stop them copying properly. If this is what you are trying to use Nero for it won't work.
If however they are your own films such as weddings, family movies etc that is entirely different.
Which is it? Your own films or movies? If its movies then its against the rules of the Forum to give advice on how to get round copy protection because copying movies is illegal.