I can't go into too much detail because of the questionable legality of doing this in the United States. You need to do two things: decrypt the DVD (if it is a commercially available dvd that has copy protection) and then copy it into a format playable on your iPod. There are a lot of programs that do this. Some do both. Some use a two program system.
Good luck
Can you transfer dvds to your ipod and if so how?

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