La Casita Blanca is great. So is La Alcapurria Quema in Santurce. Chocobar Cortes is worth a stop for lunch or a coffee/snack. El Batey, La Factoria, The Mezzanine, and The Cannon Club for drinks in OSJ; Botanico for drinks outside of OSJ (I'm sure there are more I'm missing). I haven't been, but Cocina al Fondo looks really good from a JBFA winner. Cafe Manolin is a solid greasy spoon for breakfast. SeƱor Paletas for paletas in fun flavors. ETA: Have a great time!