Belmont park is where you surf, drink beer and ride the roller coaster.

Balboa Park is where you look at old airplanes and cars, old art, old
plays (replica of Globe theatre), curious animals ("The World Famous San
Diego Zoo") and ride the coolest minature railroad around.

For camping, it sort of depends on how close to metro S.D. you want to
be.  As a displaced native, I'd suggest the state beach campgrounds.
Cardiff, San Onofre etc. The mountain campgrounds. Burnt Rancheria,
Horse Heaven and the desert campgrounds, Butterfield Ranch, anywhere in
the Anza Borrego desert. There's also the County campground at Lake Jennings.

For a kinda close but out of metro S.D. commercial campground, you might
try the Vacationer in El Cajon.  I kept my Class "A" motorhome there for years.

For stealth camping, try the Dog Beach parking lot in Ocean Beach.

Jim Arnott