I wouldn't waste my time using Nero for SVCD as I have backed up many of my dvd's and was using Nero until I discovered some of my backups were "blotched". If you're downloading SVCD from p2p clients then I recommend you use VCD Easy 1.14 http://www.vcdeasy.org/
If your backing up dvd's using DVD2SVCD then I recommend you also create bin& cue files (cd image tab folder>VCDXbuild ticked). I don't burn MPEG2 format anymore because I found out by burning bin& cue, I can scroll through the chapters, burning MPEG I couldn't. Another great burning program to use is called BurnAtOnce 0.95 http://www.burnatonce.com/index.html
Be sure that you burn NO faster than 8x to be on the safe side as many home dvd players and dvd-roms can't read MPEG2 (SVCD) discs burned at high speeds.