dvdrip is ripped from dvd max res 720x480, usually it will be downsize. but i like to keep the same pixel so i resize to 768x432 for 16:9 HDrip is rip from HDTV sources. it can be resized down to dvd res or it can be 1080i or 720p or higher
Err, the max res of DVD is actually 720x576. As for upsizing, you might want to try setting a non 1:1 PAR instead so it resizes correctly on playback like the original DVD. In theory the HDRip will be better quality, however just because the source is of higher quality doesn't mean that the rip will be.
Here's the detailed explanation for both terms: What means HDRip? What means DVDRip? Essentially, it indicates the source, not necessarily the quality. DVDRip is ripped from a DVD, meaning that its max resolution is that of DVD's: SD. HDRip is ripped from a HDTV stream, meaning that its original material has been in high definition format (720p, 1080i or 1080p), but the end file might or might not have been compressed to a lower resolution. But source material is better.