Coming to SF for 3-4 days in feb--need help
In the vein of "interesting" but not necessarily "top notch" (because that term is so subjective) Chinese, you should consider Jai Yun, Mission Chinese and Hakkasan.
For dim sum in the city, there have been (somewhat) good reports on Lai Hong Lounge http://chowhound.chow.com/topics/8664...
The 200 block of California Street (easily reached by cable car or the #1 muni bus line) has a few options for you.
For Italian, Perbacco or Barbacco are very, very good. The latter is a more casual version of the former. You will find dozens of discussions of both places if you do a serach.
For fresh fish, the Tadich Grill is a landmark seafood place in San Francisco. If fresh dabs are available, have them. If they aren't, have them broil whatever fresh fish is on the menu. It gets very busy there at peak hours. However, it is fun to dine sitting at the long counter they have there.