A useful tip

Hello. Reauthor is generally used for "movie only" backups of a DVD, where you remove the menues and everything else in order to maximize the space on the DVD-R being devoted to the movie. You can keep the menues using DVDShrink if you want to, however, by cutting out extra features (compressing them to still frames, which take up little space) and audio/subtitle streams until you are happy with the amount of compression being applied to the main title. Whether or not their will be a noticeable quality difference depends a lot on the length of the movie and the structure of the DVD (ie, how much stuff did you have to set to still frames and how much did you leave as regular video).