If you plan to spend a day in Monterey (and the Aquarium there is truly awesome), I recommend staying at this B&B: http://www.jabberwockinn.com/
It is within walking distance of the aquarium, the ocean, and Cannery Row, and the inkeepers are amazingly warm and friendly. The Alice In Wonderland theme is present but not overdone; breakfast is REALLY REALLY tasty; and they have a nightly hors d’oeuvres/cocktail/socialization hour at 5pm. Oh, and fresh-baked cookies at all hours. And decanters of brandy in the rooms. And a bocce ball court. And every room has Sleep Number Beds. And FOR THE LOVE OF GOD TRUST ME JUST GO THERE.
Husband and I stayed there a few weeks back and it was one of the best trips we’ve had together. The price is comparable to a decent chain-hotel but the service and experience makes it an incredible value.
Another vote for driving south on PCH; it’s just so much easier to use the pull outs on the ocean side. Going north, you have to turn across traffic to get to the pull outs and then again to get back on the road. Whichever direction you decide on, give yourself plenty of time; there will likely be construction somewhere along the route, not to mention slow-moving RVs that can be impossible to pass.
Point Lobos has been mentioned, it’s a spectacular spot, but note that it has limited parking that can fill up quickly on the weekends.
If you’re in to off-the-wall/Roadside America-kind of places, check out Nitt Witt Ridge in Cambria.
If you like lighthouses, Point Sur is worth making a reservation to go see.
There are a whole bunch of State Park beaches scattered along the way. Parking is expensive, but the permit is good for access to any of them for the whole day.
One good compromise is to decide which parts of the coast you want to drive on, and take 101 for the rest. it is not that far from the coast - right at it south of Santa Barbara - goes right past the Madonna Inn, and is far more interesting than 5 and far easier than the PCH. When I go to Anaheim I take 5 down, stay with friends north of LA, and then take 101 back. (The 101 south of Salinas. )
One other place to visit is one of the Getty Museums. They are near the coast, north of LA, and free, but you have to reserve parking in advance.
As much as I love SF and have spent a ton of good times in SD, LA, & OC, I’ve also spent lots of time in-between and in way-up-there northern CA. You have to decide whether this trip will be about the two cities on each end with some nature thrown in, or about nature with the two cities thrown in. Either will make a great/memorable vacation. But unfortunately, you’re right. Two weeks sounds like plenty of time until you start planning. California is a big state.
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