Can't Write DVD Movie Files

I have a Samsung and an LG CD\DVD Writer, on the same cable to the MB. I’ve had no problems until a couple days ago and I’m not sure what happened. In the past I’ve made lots of DVD’s with prepared DVD folders.
I can currently write CD’s, DVD data (ie data folders), DIVX to DVD. I cannot however write a properly authored DVD folder to a DVD. I’ve used several burning softwares and tried, but have not had success. Each time the DVD fails. I’ve used different media and all are quality media.Its as if something is missing for writing DVD movies to DVD.
Can anyone help problem solve this?

Have you tried ImgBurn 2.1.0.0 to burn the folders? you might try converting the folder to an ISO and then try burning it to DVD.

You say you have tried several burning softwares; you might want to list the ones you have tried.