Are you saying that the original didn't have the judder?
As an aside, DVD is a highly compressed format. So if you are loading from your DVD into PRE, editing and and then writing out to a fresh DVD quality will suffer. This is because PRE re-compresses footage that has already been compressed once. But I don't think this would introduce judder where there was none before.
Insanity is hereditary, you get it from your children
What type of camcorder is your original footage coming from and which project settings did you select when you started your Premiere Elements project?
I think that Neale has isolated the problem - multiple MPEG-2 compression, but if all you want to do is just make a Copy of the existing DVD, I recommend a great, free burning utility, ImgBurn, that will just make a Copy of your DVD to another blank disc. This process will eliminate one MPEG-2 compression, and yield the highest possible quality - identical to that original DVD.
As a tip, for best playability, use only high-quality blank discs, like Verbatim, or Taiyo Yuden, and burn at less than max speed. ImgBurn, unlike the burning capabilities in PrE, will allow you to adjust the burn speed.