I have found that LA driving is not as bad as people think it is. For best results, try to start your tourism day around 10AM and finish by 4PM or concentrate on weekend days, especially if your driving involves the freeways. The Getty, for example, is off the 405, so that's a good late-morning thing. The grounds are incredibly beautiful.
In and around the area you'll be (Brentwood/Westwood/Beverly Hills/the various Hollywoods), I find that east-west traffic on SMB is usually worse than Sunset is usually worse than Olympic is usually worse than Pico.