Please see all movies in their original language and read subtitles. Its not that hard :wink:
Ditto. I find that the vocal nuances of the original performances (especially noticeable in animation, of course) are often lost, and indicate more about the original director's choices. That said, if I find a foreign film interesting enough to watch a second time, I will sometimes watch the dubbed version to get a different interpretation of the characters.
As an anime fan, I am excited to hear opinions on some of my favorites (many of which have been mentioned here already), but I think it's probably more in line with the original poll question to not focus _exclusively_ on anime.
With that in mind (and considering what was already said in the podcast), a shot at a list of 6 (in no particular order):
* The Iron Giant (mentioned on the podcast; serves as a representative of the "modern" English-language family animation)
* Spirited Away (or Princess Mononoke, My Neighbor Totoro, nearly any other Miyazaki film)
* Akira (genre-changer; maybe Ghost in the Shell (?))
* The Triplets of Belleville (for diversity; critically acclaimed and somewhat recent)
* Grave of the Fireflies (perhaps the single most heartwrenching movie I've ever watched)
* Perfect Blue (or Metropolis, some brilliant non-Japanese film that I am unaware of, being an anime guy)
I could imagine running multiple from Miyazaki, but I'd second somebody's recommendation for a Miyazaki marathon. There's a significant amount of variation and depth here, and I think a chronological progression could show something interesting. It's easy to find more than 5 worth their time. (Nausicaa, Totoro, Castle in the Sky, Mononoke, Kiki, Sprited Away, and maybe Howl's Castle all deserve consideration.)
I'll say that I'm quite excited about this marathon, whether it ends up being anime-only or very diverse. If this one is not "mostly anime," then I'd be happy to see another one come by in the future.