Originally Posted by nemo
Access to a car is required in LA, mass transit/ taxi are not realistic options - unless you plan to stay within a 3-miles radius.
Getty museum and Huntington Library. Laguna beach with its art galleries, probably best in late afternoon, then have dinner at one of the local restaurants watching the sunset.
Agree re the car. I'm not such a fan of the Getty. Beautiful spot, but I find the campus sterile and have generally been underwhelmed by the exhibitions. YMMV of course, and on a nice day it's worth the trip just to have lunch and enjoy the view. The Huntington is great, especially in nice weather. (Skip the high tea, which is crowded and not very good.)
If you're staying at the SLS, you'll be ten minutes from the Los Angeles County Art Museum.
Laguna is super nice, although you'll definitely burn an entire day getting there and back, especially now that the weather is nice.
It's hard to recommend restaurants without some better idea of what you enjoy in terms of cuisine or atmosphere. The range of restaurants is pretty broad.
For a uniquely LA experience, I like the Museum of Jurassic Technology. (The name notwithstanding, it's more a long-running performance art piece than a museum per so.) It's on Venice Boulevard on West LA, so you could easily combine it with a trip down to the Venice Boardwalk, or to Abbot Kinney Blvd. in Venice, which is a popular boutique shopping and restaurant destination. (Promoting my own neighborhood here, so discount appropriately.)