personally I think nero is crap for anything except burning. Try looking at other editors/converters. Here's a list of what I use...
Virtualdubmod .. for extracting audio, editing video/audio, changing frame rates in video.
besweet .. to change the length of audio before muxing it back to the video. e.g. 23.97fps to 25fps.
Tmpgencplus .. to professionally convert avi to mpeg2.
winavi.. to QUICKLY convert avi to mpeg/dvd format, but can have audio sync problems.
Tmpgend dvdauthor .. to add chapters / menus and produce dvd format from mpeg2 ready to burn.
Nero 6 .. to burn dvd, I never burn faster than X4 as a lot of home dvd players seem to judder or stick if burnt at X8.