One day stay: Half Moon Bay or SFO ? (flight next day)

We'll be arriving at SFO around 10:30 a.m. and have just one night to spend in the Bay area before our int'l. flight out early the next afternoon. Since we have been to San Francisco several times (though it's been almost 10 yrs.) we want to drive around and just see some nice scenery, etc. The Half Moon Bay area would probably make for a relaxing couple of hours, and it has been recommended by others on this site as a good place to visit for some nice scenery. Would we really be missing something in that area if we just drove to HMB for the day but still stayed near SFO? We have reservations already at Bay Landing and got a fairly good deal price-wise. Opinions, please!