http://www.erightsoft.com/SUPER.htmlThis converter is working great for me so far.
1. Convert to iPod-Compatible format (Super Converter has iPod and iPod 5.5 [640x480] presets so all you have to do is drag in the video file and convert)
2. After encoding is done, drag the file into iTunes Movies section.
3. When you plug in your iPod, just work around with the settings in the Movies section. It should be user-friendly enough.