Aha! I posted a similar sort of topic (http://community.livejournal.com/indeedsir/797500.html) a while back, prompted by the thought of Fred Astaire as Bertie. This is now leading to musings on a J&W musical version... mmm.

Alas, I suppose we are talking about actors who are still alive and young and dashing... to which I simply counter with the idea of a time machine (or, you know, a TARDIS)!