The resort is actually supposed to be pretty nice. The Wild Animal park isn't really all that far. There's a casnio out near there somewhere as well, I've never been.
They're just over the hill from Temecula and they have vineyards and wine tastings there if that's something they might enjoy.
The
Stone Brewery is also in Escondido. They have tours and a really good resturant - make reservations or it can be a long wait. (call for directions your GPS will not get you there - nor will googlemaps)
They're really only a half hour or so from Downtown as well.