As others have said, it's not even a question.

Dr Manhattan isn't afraid to reduce anyone to a puddle of themselves. Superman doesnt fight to kill. Even if he did he still wouldnt put a dent in Manhattan.

A fight between Dr Manhattan and Superman, should last just about as long as a fight between Batman and Superman.

a fight between superman prime an doc Manhattan would have been better

Goku would beat Superman with a fingersnip and then Mr. Manhatten would wink and Goku is gone. That's the power differentials we're talking here.

Doesn't matter. Goku would beat both :p

Goku would beat both, wake up from his dream and realize he's still in a body cast from his first confrontation with Superman.

But on topic, Dr. Manhatan has been, pretty much, conceived as godlike in just about any sense of the word. It's like pitting Superman up against the Presence.

Dr Manhattan's penis.

Dr Manhattan easily

Batman