Seriously he’s (she’s?) absolutely right. San Diego is what you’d get if you took L.A. and halved its population, doubled the amount of public beach, threw in an enormous bay* and a huge marina, took away the smog and added five degrees to the temperature. I"m still pinching myself that I live here now, and I live 22 miles inland. But if I want to enjoy the ocean, it’s less hassle to get to it now than it was when I lived in L.A. and was only a few miles inland of Venice.
If you want to be near the beach, and I assume you do, it’s a good idea to stay at one of the Mission Bay resorts; in particular, one on the western shore because that would place you within two blocks of Mission Beach. If you don’t want to spend that much, you should still try to be as near Mission Bay as you can. When my brother and I were kids the family spent a few days at Mission Bay, and a great family activity that we all enjoyed was sailing. Sailing Mission Bay is easy and one lesson was enough for us to take a boat out on our own, provided we stayed within the bay.
The San Diego Zoo is a must see, of course, and so are some lesser known attractions which are also in Balboa Park. A favorite of mine is the Timken Gallery, a privately owned and operated art museum specializing in Old Master paintings. IIRC unlike the public museums, admission is free but parking, probably, not so much.
If you or anyone in your family is into classic cars, you might want to come up to Escondido, which is my neck of the woods, on any Friday for the weekly Cruisin’ Grand event. They don’t actually cruise; instead dozens of vintage cars are simply parked in the downtown area and you can stroll around and check them out, and talk to the owners if you’re into that. Some are stock, others are variously chopped or modified, but they’re all beautiful. In fact, here’s a link to the Flickr album I put together last year:
[link=Cruising Grand Escondido | Flickr]Cruisin’ Grand
Escondido is also the home of the SD Zoo’s other facility, which used to be called the Wild Animal Park but is now the Safari Park; there are also a few wineries in the area. Whatever the reason, if you decide to go anywhere near Escondido or elsewhere in the inland, be prepared for very hot weather.
In general, California beaches tend to be grey and fairly cool in May and June, so the later in summer you can come here, the better.
*In the early days, San Diego was boosted as the Silver Gate, being the second largest natural harbor after San Francisco. The only reason this harbor and the town next to it didn’t keep pace with the growth of population and business in L.A. was that it didn’t get its own transcontinental railroad link.