Things to do in San Francisco.?

Hi! Im from Mexico City I will be five days in San Francisco, I would like to know the bookmarks I must visit. One of these days I hope I will go to the AT&T Ball Park to see the champs. Where can I buy tickets the day of the game? Also I need sports memorabilia stores. I would like to know places to go shopping, museums, attractions, restaurants and bars. It is my first time in SF and I want a nice experience. My hotel is next to the Westfield mall. Thank you very much!