Shake his hand?
Ask for an autograph?
Give him a kiss on the cheek? *Shimmy!*
Tell him, "This is an incredible honor, sir - you are one of my great heroes!"
Well, that's what I'd do - probably all four. I certainly would not say, "Tell me about the orbiter being faked," or call any of them a "coward, and a liar, and a thief"!
It's kiss-an-astronaut day. Despite NASA's current (and huge) problems, these guys still have the right stuff. Holy crap, do they!
Shimmies to Rev. BigDumbChimp.