Cocktails, Fun Atmosphere: Aqui's (Willow Glen) - http://www.aquicalmex.com/
(I prefer the Willow Glen branch because the crowd is, like me, a little older. If you prefer a younger crowd, try the one in Campbell. Watch out for the tasty "Swirls" cocktails. They're super strong but don't taste like it!)

Bourbon-Centric Sportsbar: Bourbon Steakhouse - http://www.michaelmina.net/restaurants/san-francisco-bay-area/bourbon-steak-pub/   (great to watch sports, impress a client, wide variety of bourbons, but not cheap)

Wine Bar: Vino Locale - http://www.vinolocale.com/  (hang out, talk with friends, good wines, appetizers, sometimes mellow live music on the rear patio)

Beer Garden: Steins Beer Garden  - http://steinsbeergarden.com/

Trendy Cocktail Bar: Straights (Santa Row) - http://www.straitsrestaurants.com/location/straits-santana-row/  (trendy, cool place to hang out. Turns into a club atmposphere later at night, about the time I go to sleep)