Seems your interest lies in American junk food, not our multitude of cuisines...that's probably a good thing since we don't think Orlando is the best place to get authentic American cuisine. Well, at least not the touristy areas.
You may or may not have these down under...my work colleagues in Melbourne only talk about beer so I've no idea about 'normal' food for ya'll.
1) Warm Apple Pie or Apple Crumble with ice cream.
2) Candy or Caramel Apples.
3) Frozen Chocolate Bananas.
4) Turkey Legs (not really junk food).
5) Any snack product from 'Lays'...they're one of the few national brands that make pototo chips (crisps), taco type chips, various salsas etc.
6) Hershey bars.
7) Any candy in the store on Main Street.
8) Any beer that is a 'porter'. Mostly dark beers without the weight of a stout, made in either the lager or ale style depending on the brewer.
9) The Kitchen Sink at Beaches & Cream at the BeachClub.
If you were coming to Philadelphia, I'd add cheesesteaks (1 word), Goldenberg peanut chews, Tastycakes, soft pretzels, scrapple, and pork roll.
Happy munching.
Joe