you can backup a dvd to cd BUT. a dvd contains most 4,7 gb and a cd 700 mb so you have to delete some things. Most of the time you delete music movies. It`s also possible to downsample them. This means you don`t have to delete them but the quality will be a lot worser. From dvd to cd is calllad ripping. Go to
http://www.psxcopyworld.co.uk/ and check it out. you`ll find the rest of the info there.