Pretty much all modern HD's automatically park their heads in a safe position when they're turned off. In fact, I think that the only HD I remember that didn't park automatically was on my wife's 386 PC while we were still in college. Just try and keep your iPod's original boc around, that should provide sufficient protection for shipping.
Anyway, use CD-R or DVD-R, as long as your friend has a computer on the other side of the world to read them. Not only would that be cheaper to send, but the customs inspectors will be happier...