Tough call here!! In a battle of wits though, I'd have to give it to Sheldon.

Joss Whedon vs Matt Vancil

Whedon would eat Vancil alive, and still manage to offer snappy, well-written dialog while doing it.

Vincent Price (in his prime) or Christopher Lee (also in his prime).

Doctor Monroe could have his Monsters do the fighting for him. They outnumber frankenstein and are animals so very strong. So DOc Monroe obviously wins.

Price vs Lee ends in a tie or draw if your prefer. They both end up retiring to Price's mansion for some man love.

Chris Lee wins with his new weapon, the Weapon of Choice.

Giuseppe Garibaldi vs. Francisco Franco

Franco because his full name was much longer and more impressive.

Bruce Lee versus Frank Mir

Bruce Lee, he fought Chuck Norris and lived long enough for the tale to be heard.

PCs vs NPC.

PC. NPC's don't get munchkining

WoW versus GW2

WoW. Its pay to play model nets it tons o cash from golden oldies.

Furry hat vrs furry boots.

Furry hats, they come with vikings.

Aragorn vs Taran

Taran, because he has cooler pets.

Simo Hayha vs. Carlos Hathcock