Black Ops Pc still not working.?

I bought the game soon after it came out and i still cant get it to work. I havent tried to fix the crazy MP lag yet but thats not my main problem. The problem is a cant do anything in the Campain or Zombi stuff. i can get to the main room but once i click on campain or zombi thing it will do its little story line speal then crash. there used to be some server error thing that popped up but now i cant even see it and i cant use my computer untill i ctl atl del and end the black ops. PLEASE HELP BECUASE STEAM WONT. is there a patch i can be directed to?