you'd need the appropriate video codec to decode the original streams. Assuming you're trying to burn to dvd (for playback in a normal dvd player) you'd also need any dvd authoring software. Assuming you have that and that's what you want to do, all you need is xvid.

If you're just trying to dump off a couple data dvds, you don't need the codec installed to do that, but you'd still need it installed to play them. Also, be aware that you should be able to fit something like 26 episodes to a dvd as a data dvd, where you'll probably only get maybe 5 or 6 at most on an authored dvd. So it really depends on your purposes.

And for a point of accuracy, "ripping" always involves getting stuff from a less malleable format into a more useful one. So, getting video off the dvd onto the hard drive and decrypted, or getting music off the cd, or whatever. What you're trying to do is either simply burning (for data dvds) or dvd authoring (for dvd-player playback).

Also, it's notable that you'll probably need about a dvd's worth of free space to actually author the dvds (since you're reencoding them), and it'll probably take significantly longer to do so.