Peanut butter is crushed peanuts... I don't really see how it could vary that much.
Sometimes it's sweetened... which, again, doesn't seem like it would vary much.

As for the peanut butter and jelly sandwiches, I confirmed that all of my UK friends have indeed had them. Or at least they've had peanut butter, butter, and jam, between two slices of white bread.

As for fried chicken... I get the impression it's just as common there as in the united states? Stuff like KFC and the british chain "Nando's".

Chili, at least home made chili, is something my boyfriend has been exposed to at least.

As for hot dogs and burgers... it's meat in a patty or tube shape that's cooked and served with bread. It's about as region specific as a pot roast.