Jules Verne. I love his stories and would like to see what he would come up with for new stories after taking a look at how things have advanced since his time. 
A nice quiet month-long historical interview (de-briefing?) with Alexander the Great. Doggone, that would be fun!
Wouldn’t it be great to explain to George Lucas that his movies would inspire threads like this one?
Mozart or Bach. Probably Mozart… Bach was a bit of a stiff, while Mozart would probably die even earlier from all the hard-core partying.
Gut feeling-but Ben Franklin would adapt and not go immediantly insane at being transported into the future. Electricity, speed of travel, Ghengus Kakn = sword through your gullet.
He’d be wondering why we let the Jews loot our economies and why we didn’t follow his sterling example. Then again, he might come to enjoy the more convoluted and conspiracy minded racism. Big fan of the Turner Diaries, I bet.
While I’m not complaining about bringing that thread up from the depths, technically George Lucas isn’t actually dead yet.
I wouldn’t mind seeing what Hypatia could do with the opportunities a modern education, and today’s less rigidly defined gender roles, would provide. It’d let us see just how good at math she really was.
Seeing what Shakespeare would do in today’s media industry would be a kick too.
I agree with QuickSilver that Jesus’s reaction to what his teachings have brought about would be hilarious.
Newton. First off, once he gets up to speed with modern chemistry he wouldn’t spend half his working life dicking around with alchemy. Second, can you imagine what he’d be capable of with a little computerised assistance?