It depends on where you are and what type of house it is, but, in Britain at least, we use the Spanish word 'patio'. If it's a hard-surfaced area (tiles or concrete as opposed to grass) , where you might have garden chairs and a table, or a barbeque, we'd call it a patio. A playground is a large area, often a public place, in a school or a park where children can play. Courtyard suggests an area enclosed on three or four sides by walls, part of a castle or another large traditional building.

We also use the word 'patio' in the United States. In the South, we sometimes say 'porch' to refer to the same thing.