I wouldn't recommend installing codec packs as u end up installing alot of codecs you don't need. maybe this method resolved the problem on your machine but may have adverse affects on someone else's machine. Remember ONE thing when installing codecs: only install the codecs you need, having more is not better, at least not with codecs.
The reason why Nero Vision Experess 3 is freeze or erroring is because of the video codec Nero uses to decode DVD. That codec is Nero DVD Decoder and Nero Video Decoder if you can disable it from running your problems will be solved. The only media player I know of that can single out particular codecs from running is The Core Media Player. When I disable Nero DVD and Video Decoder from running the freezing and errors stop once I enable them again the freezing and error comes back.