I would recommend the La Jolla Shores Hotel for location.

The Hotel La Jolla is not an easy walk to the beach and it is situated on a rather nightmarish intersection.

There are a couple of smaller hotels down in La Jolla (on Prospect) the names of which escape me but those would also be good, location wise, as they would leave you with more to do (other than lounge around the beach or pool) than La Jolla Shores.

These are assuming you want an actual beach to frolic on. If not, then there are some nice hotels down around Petco Park (the Omni comes to mind) that are a short walk to the embarcadero and Seaport Village to get close to the water, but are also surrounded by restaurants/shops etc.

Either way, enjoy SD.