Despite the fact that he was intently watching everything that was happening with a sense of shared horror and stunned amazement, there was no hesitation in him at all when she told him to run. He had no desire to stick around and find out of the ghost would come back again.
What he did do, though, was as he was running through the door, Ted gripped onto the girl's wrist to drag her along. She wasn't going to stay inside the house any more than he was. At least, not while he was around. Not after he'd watched her being slammed into a wall like that. He didn't care if she did have a gun, and if that gun had some ability to make the ghost vanish for a while.
Ted didn't stop until he was down the stairs and in the lawn. His heart was beating wildly. He could feel it in his fingers and toes, and hear the blood rushing through his ears.