Well if some of the files you burn will work and others will not ( and they are the divx format of course) it might just mean that you
sometimes will not get a successful burn every burn....If you have a spec of dust on the Media you are trying to burn on it can mess up the process. My advice is burn it again.
OR try Easy avi Divx Xvid to DVD burner, OR Nero if you think that is not the problem