How to move videos from an iPod to computer?

I've tried several ways to do this, but none of them work. When I move the videos directly from my iPod to my computer, my drag and drop or through a program on the computer, they all become corrupted. Either the video works and the audio doesn't, or vice versa. I've even tried emailing them to myself, which works for short videos, but I can't only send about a minute long video via email. It's very frustrating. Can someone please help me?