In both Glasgow and Edinburgh, we have Lupe Pintos, which is mainly a Mexican ingredients shop, but has some American stuff, as well as some Spanish items.
Glasgow also has at least one American candy shop... the one I've been in is called Gobstoppers and it's across the road from Argyle Street station.
Just outside of Glasgow, in Giffnock, there is a Whole Foods market, if you're into that.
A Taco Bell is due to open soon in Glasgow, in Sauchiehall Street, and we have things like Byron Burgers and Five Guys.
Games & movies? No idea. Aren't games and movies fairly universal now? What they have there, we have here? I really don't know.