Wow, I am envious. I am from the Bay Area, and miss it. Used to live in Reno, too -- you definitely need to visit Tahoe.
If you are spending time in SF, there are obvious tourist places to go -- Fisherman's Wharf, Golden Gate Park, etc. You should also try to go to the Palace of Fine Arts. If you like science, there is a museum there called the Exploratorium that's a lot of fun -- all hands-on exhibits, built mostly by scientists and science classes in the Bay Area. Worth the trip, believe me. If you are travelling far north, a trip to Mt. Shasta (and Lake Shasta) is very nice, too. You can travel through Napa Valley, and stop at a few wineries for tours and wine-tasting 🙂