Hand to hand, though? Easily, Batman. Easily. Outside of cut scenes, Snake's a pretty average fighter. In-game, if you somehow have no weapons and are forced to fight a group of twenty guys you are S.O.L. Batman eats those kind of odds for breakfast. The game's actually kinda boring if you have to go against a group that doesn't number in the double digits.
Again, it seems I'm the only person defending Snake, though, in actuality, Batman would probably win just based on the fact that he's not a dying old man with three weeks to live. The reason why Snake couldn't beat 20 armed opponents is because he's not fighting random thugs, he's fighting experienced soldiers. When is the last time Batman did that? In fact, how often does Batman fight any single person, much less an army of them who's a halfway decent shot? Now, assuming anyone has such an example, when did it happen without the cover of night and his fancy toys to swing around with?Snake's not even the best hand-to-hand fighter in his own game! Grey Fox or Raiden would tear him to pieces if they were forced to fight in a single room unarmed.
Ironic, because that very thing happened, and Snake won.
Look, I'm only really defending Snake because I'm at work and I'm bored as hell, and in all honesty Old Snake without his medicine would spazz out and die from his nanomachines even if he won. Old Snake is a dead man either way!
I'm pretty sure Snake still had access to his equipment during those fights, though, and that's really all this quiz is asking.
Unfortunately I don't have an extensive knowledge of all things Batman to dig into in order to find a perfect example of him defeating a skilled opponent without the use of any weapons whatsoever. The best I can think of is one time he fought Ras al Ghul after being stripped of his utility belt (and after al Ghul had de-aged himself) and managed to win. I know he beat Captain America once, but he did have access to his utility belt at the time, and Cap still had his shield. He did take down Guy Gardener once with a single punch after Guy agreed to fight him without the use of his ring.