Whenever I travel to LA on business I usually find myself estimating at least 1.5 - 2 hrs extra no matter where I go whatever time of the day. Seems I might have bad luck, or maybe it's everyone, but I always hit traffic no matter what. :/
Take the metro! It goes pretty close to where you want to go..Although it'd be green -> blue -> red...maybe not such a good ride, that green -> blue is a bit sketchy..and blue -> red transition is downtown.
I'd say just take a cab or one of those shuttle vans.
Cabs can be expensive. I travel every week and let me give you a tip with those shuttle vans. Don't. If you are heading for a flight, especially avoid these. I learned early on in my career that it is a bad idea. They neglect to tell you that they stop at, on average, 5-10 hotels on their way to the airport. They are incorporated but individually owned and operated (in most cases) and therefore it is most effective for them to pick up as many passangers as possible per load to maximize profit for trips. Especially with gas prices as they are in most states. My state, no the case. In OK gas where I live is now $1.85 per gallon.