There should be no different in the basic process of burn to DVD in Premiere Elements 12/12.1 and 14/14.1.
But, before going further, we need to clarify what you want to do.
There is no burn to disc ( DVD-VIDEO on DVD disc or AVCHD on DVD disc) which offers 1280 x 720, either version of Premiere Elements. And, Premiere Elements does not offer burn to data disc for a 1280 x 720 file.
Consequently, please explain and give more details. If you have questions or need clarification on the above, please do not hesitate to ask.
Thank you for your reply.
I have video in 16:9 format from my camera and have successfully written these to DVD on Premiere Elements 13 for playing on a DVD player but this is the first time I have used Elements 14. I did successfully make the video up of several films this morning in Elements 14 but the problem was that it would not burn to DVD. It plays from Elements 14 fine and the DVD will play on the computer fine.
I hope this explains better.
Nero has just done the job fine so I have no idea why Premiere Elements 14 will not do it as 13 did.