If you want to copy data, then you can just copy and paste the files. If your talking about DVD Video(e.g. Day After Tomorrow), then you need a program that copies it, i found a really good one called DVD Copy Tools (You can search for it on altavista cause i forget the link). And not that im for piracy, but this program removes the CSS encoding, so you can use a recoder(Nero Recode) and make a copy of it for your own personal use.