For anyone wanting to help......... it would be good to know some particulars, like: What computer? (Desktop or laptop.) OS, version? What speed are you trying to burn at? Have you used the same burner and software under XP, Vista or win-7?
Always remember, "A slower burn is a better burn".
I use only two programs for burning DVD's on my computer. "Nero", which I've used like, , , FOREVER! and "ImgBurn" which I only use for burning .ISO files to CD or DVD. It also works great for making an ISO off of a CD or DVD.