The ISO files are actually less than DVD quality. They are 480i, which is worse than 480p. To convert using Handbrake, you will need to enable deinterlacing, otherwise the resulting video will have deinterlacing artifacts.
I agree with Avvilimento, be wary of "fast" encoding. If you really want to save space, you should choose slower settings because it will result in a smaller file for the same quality, or higher quality for the same file size.
I agree with Avvilimento, be wary of "fast" encoding. If you really want to save space, you should choose slower settings because it will result in a smaller file for the same quality, or higher quality for the same file size.