I think you're an idiot. The equivalent of this match-up is you fighting Robo-Cop with a stick. Whether you have the stick or Robo-Cop does is irrelevant.
Considering the Spartan IIs have genetic and cybernetic enchancements, plus the greater technology. I'd say them. A spear against a piece of steel surrounded by an energy shield probably wouldn't work too well.
Also, 300 spartans are just plain spartans(well spartan warriors). 300 was loosely based off the Battle of Thermopylea. While probably not as comic book heroic in real life, they still share many traits, however romanticized one of them might be.
i think its funny that people think this is a " who would win in a fight? a 300 spartan or a halo spartan?" thread.
its not XD
to make it simple, its kinda like a "who did their job better?" or "who do you like more?" thread.