I think the fight probably would have turned out roughly the same way. Most of the pertinent information came from Ma and Pa toad. The only piece of information Naruto wouldn't have had was the time delay between Shinra Tensei uses.
Since Naruto wasn't in the village during the attack, Pain probably would have crushed the village and left, assuming that he had killed Naruto. He might have left a few of the paths behind to clean up and make sure, but I doubt he would have left all Six Paths there. Naruto would have come back to the village in much the same manner, but instead of Pain being there ready to fight, Naruto would just find everybody dead. If some Paths were still there, Naruto could probably handle them. Then he would hunt down Nagato and slaughter him.