Ubuntu: Connecting to a Windows Network Printer
To allow Ubuntu or Linux PC to Print to a Windows Printer, you must enable LPD on Vista , and Unix Print services on XP.
How to Enable LPD on Vista :-
Control-Panel-> Program and Features -> Turn Windows Features On and Off -> Print Services -> LPD Print Services (Click to Enable)
This done Ubuntu will be able to see your Printer on the Network.
LPD is short for line printer daemon