I would ask him if he believed there was hope for peace and equality between the peoples in the world sometime in the future. From his participation in Fraggle Rock, I have realized that this is a hope that both Jim Henson and I share.
LOL, made me laugh, but then, I have a twisted sense of humour
I think the point of not asking about puppetry, is simply to add a twist to the topic's question. Obviously, the first thing most people would do if they met Jim is ask about muppets and stuff, I know I would! ("Mr Henson, may I please touch Kermit... pleeeeaaasssee??").