What is your burn to
DVD-VIDEO standard or widescreen on DVD disc?
AVCHD format on DVD disc?
Blu-ray disc formaton Blu-ray disc?
Have you updated Premiere Elements13 to 13.1 yet using an opened project's Help Menu/Updates? Is Windows 8 32 bit or 64 bit?
When you do the burn to, what are the Space Required and Bitrate readings with and without enabling "Fit Content to Available Space".
And, what is the video card/graphic card that your computer uses? If not one of the Intel HD Graphics 2000 and higher cards, then disable the preference related to that card in preferences. Please see Edit Menu/Preferences/General and "Use Hardware Acceleration (works on Intel HD Graphics 2000 and higher)".
Please consider, supply more details, and then we will decide what next based on the details in your reply.