Since video quality is very subjective, I would suggest making a short conversion (using the chapter range selection in DVDFab) using the different settings to see if the smaller/faster setting is adequate for your needs. For the testing, select a chapter that is stressful to convert, i..e. one with lots of fast motion and fine detail. You can also experiment this way with smaller output screen sizes, such as 1280xX or 1024xX, which your player will upscale on the fly to 1920x1080 or whatever your display requires. This will have huge savings in conversion time and output file size if the video still looks OK to you.
