Browsing on phone at the moment but will put links in later. Not sure what container or codec you're going for as end result but would advise a chain involving:
You could automate relatively easily as both AnyDVD and DGindex support command line switches andavisynth scripts are just txt files with an .avs extentsion. Can't remember if MeGUI supports CLI, but it does allow queuing. Alternatively, swap MeGUI for x264 and that supports CLI (and I find results are better).
EDIT: Back on PC now. The AviSynth script you want will be:
720p frame size is 1280x720. The goal with resizing is to maximize either width (widescreen films) or height (fullscreen films) for the desired resolution while keeping the Aspect Ratio as close to the source as possible (never lower). The equation for this is fairly simple:
For instance, I have a source which is (688,560). I would therefore end up with the following if I wanted to resize/upscale:
My final .avs would therefore be for a 720p encode (after rounding down to nearest even):