As mentioned in my previous post, if you have QuickTime Pro, this is all you need to do (see image below.) QT Pro also gives the iPod export option to some other mac programs that use QuickTime for exporting.
_____ File menu -> Export.
Keyboard shortcut for Mac is
Command (Apple key) -
E _____⌘ E.
_____ If Movie to iPod is not already selected, then select it from the drop down menu in the Export window.
MPeg 4 & H.264 will also import to iTunes & iPod however, the video dimensions, etc. must be exact for iPod which is why it's best to choose the preset of Movie to iPod to make sure the file is converted in a way that makes iPod happy.