Can i put dvds, or youtube videos on my ipod video?

I have an ipod video, but i have never used the video part, I dont want to buy stuff off itunes, when i have plenty of dvds that i bought. Can i put them on my ipod video? I saw someone the other day who had south park episodes on his ipod video. If anyone knows how to do this plz respond thanks.
I am looking for a software that is of the following:
1. Completely FREE
2 No watermark when viewing (like a demo sign)
3. High Quality (full screen, color, sharp image…etc.
4. converts both dvds to ipod video, and youtube videos to ipod video

also what is a youtube video an mpg?