October is a great time to visit SF! It's usually very sunny and pretty that time of year.
You should DEFINITELY plan to spend at least a day in Napa or Sonoma. If you are coming for a while, plan to go on a weekday, because it's really crowded on the weekends. Also consider taking a tour or the little train that goes through Napa, since you'll be drinking wine all day!
There is also a 49 mile drive through the city that hits all the highlights. I am pretty sure you can rent a go-kart for this, I see them zipping around all the time.
You can also drive up highway 1, which runs along the coast. It is very beautiful.
There's also a lot of good hiking in the area, the museum of modern art, the Asian art museum... what kind of stuff do you like to do on vacation? Spa? Shop? Hike? Putter?
Trolley rides are a must too, just to say you did.
Oh, there's also the curviest road in the world - that might be part of the 49 mile drive. In any case, you can walk up/down it as well. It's been in some movies. There are also a lot of walking tours.
Even when it's warm in SF, it's a little chilly, so definitely bring a sweater. That's one thing that drives me crazy about this city, in the sun you want your sunglasses and no sweater, and the second you're in shade, you take the sunglasses off and put the sweater on. Then you go into the sun and put the sunglasses back on... you get the idea.
Are you bringing Jackson???? Depending on when you are here, there might be a yorkie meetup!