For .vob conversion, I hate to sound sloppy, but I just click on one file in the folder [an entire folder full of sub-files for one single vid], and it converts the entire folder bundle into a neat single mp4 file.
And cuts the size from 4GB to 1GB.

That's quite a difference for mpg.  Have you looked at the results upconverted to HD? I'm just curious about the quality loss.  I know .mp4 can squeeze HD mkv into a lot fewer bits.  I'm just wondering about standard DVD though.