This is LA, what isn't there to do?!
From theme parks, to beaches, to Hollywood, you name it, LA has it.
New Port beach is by far the cleanest and prettiest in the area.
Venice beach is better to visit on the weeknds, this is when they have more venders and curiousities.
Sunset strip at night: visit the rainbow bar and grill, whysky a go go are popular muscian hangouts
Plenty of great parks and hikes in the area