How do I download media from the Internet Archive to my computer and then iPod/iTunes?

If you haven’t already see the Internet Archive, get over there. Lots of very cool media from way back.

There are also some great movies in the public domain that I’d like to download to my external hard drive (and later to my iPod) but I’m having trouble navigating their system or making sense of their instructions. Can someone explain the process to me in words of one syllable or less?