Please post a couple of items from the burn log, which can be found at C:\Documents and Settings\..username...\My Documents\DVDFab\Log\ This is a text file that you can open with Notepad and copy and paste a few recent entries into a reply post.

if you havent already, please read the official guide.
http://www.dvdfab.com/docs/

i have a video showing what settings i use. these work best for me.
http://youtube.com/watch?v=Eu3KMtvEaHM

im sure this is not your first dvd program you have tried using. not knowing what else you have installed, uninstall what you dont need. then follow a nice guide from stormjumper for how to uninstall / reinstall dvdfab.
http://club.cdfreaks.com/1711788-post1.html