Older people tend to say "pictures" instead of "movies", although this is disappearing as few younger people say it any more. Some older people even say "filims" [sic].
Also, (this tends to be amongst posh people), mall isn't pronounced "maul" but "mal".
The closest thing to an American "biscuit" is a Yorkshire pudding. To Americans, pudding is something sweet and running, and you don't eat with your dinner.
Oh, that reminds me, "tea" can not only mean the beverage, but the evening meal.
Chips aren't french fries. They're both slivers of fried potato, but chips are shorter and fatter than french fries (also known as "shoestring fries").
Other uses of "mum": it can mean to be discreet, "Mum's the word". Also, when someone serves tea and offers to pour, they are "being mother".
Here in New Zealand there is a company that makes "elevators" named Schindler. During the 90s they would sometimes be defaced with the words "Schindler's Lift".
We tend to say soft drink or fizzy drink for "soda", not sure if the British do too.
For pavement, we tend to use footpath. Concrete is just what it's made out of.