When at Disney World, look for people dressed like this:
Disney Photographers. They are your friends.
For one thing, they know a lot. Like, they can tell you how to cut across the Magic Kingdom in the middle of a parade without losing your life. They'll know where to find the funnel cake. They can answer many of life's deeper questions.
Mostly, though, they come in really handy when you want a photo. They walk around with crazy camera equipment offering to take photos of people in strategic places all over the parks. When they take your picture with their cameras, the images are linked to a card which they will give you. You can later access the images online and order any prints that you want. That's handy if you forget to charge your camera battery (Not that I've ever done that. Ahem.), don't have a good camera, or just don't want to be bothered with being the photographer.
However, if you do have a camera, any camera at all, and you want to be included in a photo, go find one of the Disney photogs. They will happily take a photo for you using your camera. For free. Totally free, no strings attached. Keep in mind that they aren't going to try to figure out how to use your camera, so you want to make sure it's all set when you hand it to them. Still, it's an easy, stress-free way to make sure you get a few family photos while roaming the House of Mouse.