When I try to put a 320X240 movie on DVD, the authoring software (TMPGEnc as well as Roxio) “stretches” the video to full screen. The resolution of the video can’t handle this so the image quality is very poor. Anyway to put it on a DVD and leave the image “unstretched”?
Rhe answer is no if you want to make your disc compliant.
35ax240 is a complian DVD size (as an MPEG1 stream) but 320x240 is not. You can try using DVDLab, as it can relax the dvd specs and allow an authoring, however, it may not play on any DVD Player.
You could use Avisynth for adding a border and then frameserv it using VirtualDub into an encoder such as TMPGEnc Plus. According to dvdrhelp.com MPEG-2 should be fine at the res ChickenMan suggested (352x288 for PAL).