San Juan/Isla Verde
Rent a car from Allied Car Rental or Charlie's car rentals, where they usually have decent prices on Jeeps and convertibles, and drive east out of Isla Verde along Route 187 toward Fajardo. If you have a 4 wheel drive vehicle, you can see small sand entrances amongst dense trees that you can drive into, leading you to semi-private or private beach areas. These areas aren't great for swimming but you can certainly cool off privately or stop for a picnic.
See also "Get Around" "Rental Car" under San Juan for driving there.
Go to Espana Bakery. On the south end of the highway (west end of Isla Verde) it has been in existence for over 30 years easily the best place to get "pastelitos" of many types, Spanish style soup (Fabada Austriana or Caldo Gallego - both are versions of hearty bean and ham or sausage soups), sandwiches and "cafecito" the local coffee drink drunk any time of the day or night.
The area holds many excellent hotels and condominiums; some of the latter offer units for rent. Hotels on the beach often charge higher rates than others. Hotels near the airport usually insulate rooms effectively against the noise of aircraft landing and taking off. Nearly all are within walking distance of a wide range of restaurants, from fast food to island specialties.