Fitting contents onto a regular DVD

I have some DVD files in both an Audio & Video folder that total about 6.8GB. I need to put these files onto a DVD for playback in a standard DVD player. Its obvious it was intended for a dual layer disc, but what is the best way of making them all fit onto a standard 4.7GB DVD in one step. I realize the quality might be sacraficed, but that is OK.

I would try importing the files with DVD Shrink, it does a descent job at compression.