Best beach for kids: MARINA DEL REY - The beach has a sheltered cove so there is no big wave for mother to worry about the kids in the water.
Coolest beach spot: MANHATTAN BEACH - home of famous LA athletes like Shaquille O'Neil. The beach scene resembles an episode of Baywatch. It's mostly a mid-20's crowd at the bars and night clubs. El Porto Street is known for its great surfing and boggie boarding. There's plenty of jogging and rollerblading along the Strand, which runs along the beach front. There are plenty of beach restaurants in this small, yet popular beach community.
Most eccentric beach: VENICE BEACH - You'll be entertained by just walking up and down the beachfront walk. Beach front or "street" performers and flea market type bargain shops rule this artsy community. Home of the famous outdoor Venice Beach Gym. This beach has been seen in endless amounts of movies like White Men Can't Jump and TV shows like Pacific Blue and MTV's Real World. Maybe you'll even run into the turben guy on roller blades with the electric guitar, or at least lots of women struttin' their stuff in those California thongs.
Best surf: HUNTINGTON BEACH or ZUMA BEACH.
Best all around beach: HUNTINGTON BEACH! This place has it all. My sister used to lifeguard this beach and lived right around the corner from the pier. She will boast about the nightlife, restaurants, friendly people, daily entertainment, shops and sunshine. And the water is nice too!
Next best all around beach: SANTA MONICA - Santa Monica State Beach is one of the widest and most popular beaches in the Los Angeles area with everything from an amusement park on the pier to volleyball. I lived 9 blocks from the beach in the 90s and loved the location! The bike path goes for miles directly underneath the Santa Monica Pier north and south with an easy ride southbound to crazy Venice beach. On the pier, the Pacific Park amusement center offers a nine-story Ferris wheel that provides a bird's-eye view of the city and coastline. There is also a 1920s vintage carousel, plus skeeball, air hockey, pinball, video games and more. A bait and tackle shop on the pier serves fishing fans. Shack shops serve snacks of raw octopus. Not far is the original Muscle Beach. There are free live concerts Thursday nights during the summer months. Just stay out of the water; it tends to be dirty and pretty nasty.
Gay beach: LAGUNA BEACH has always been known for its gay community. But, after all, you're in Southern California, so there's a gay population at each of the beaches. Laguna beach also features great art collections and shows from local artists.
Just south of Laguna Beach is a little place called CRYSTAL COVE. It's somewhat isolated and is lined with beachfront homes, one from the movie beaches. That for sure is my beach of choice. Good surf, clear water, no crowds and great sun.