You cannot swim at the other resort pools. Beach/Yacht club also has zero entry. I know the Holiday Inn Family Suites (now Nickolodian hotel) also has zero entry (My kids loved that pool).
About the campfire we did it a couple of years ago but I think it started around 7:00-7:30, they did the singalong, then roast, then watched the movie, you could leave before the movie. The only thing you get charged for, is if you buy the marshmellows and stuff (which you can bring if you want). They didn't start the movie until it started getting dark.
We loved it and will do it again. But it was difficult getting in and out of the campfire area. You need to take a bus to and from your car and do a little walking. At night it was very dark when leaving, we just followed some other people back to the bus.