I spent 3.5 years in the Bay area at Santa Clara University. The city (SF) is a great place to visit. If you want the best Italian dinner in town, just off of Broadway in the heart of downtown is a restaurant called "the North Beach Restaurant." The grand parents' of my best friend in college owns the restuarant. Best food I have EVER had---always voted best Italian in the Bay Area. Better there like 30 years or something. You will not be disappointed. Stay away from the 'tenderloin district' for obvious reasons.
Tons of nice little bars and pubs down there...very few corporate owned restaurants and bars down there...all places that have been there for years...most were rebuilt 80 years ago after the earthquake and just continue to prosper.
Enjoy your visit--check out a Giants game if you get a chance-- the park is bad ass.
Roln 20s