Did dinosaurs used to hunt and eat humans?

No, at least if you count only the classic dinosaurs (extinct 65 million years) and the genus Homo (appearing 4 million or fewer years ago). However, THEIR descendents may well have chowed on OUR ancestors, and vice versa. Obviously, we eat birds today (thank you, Colonel Sanders) and once in a while a bird may have gotten the upper hand. Giant moas survived until historical times and "terror cranes" were coeval with primitive humans.