Once I write Shift 2 it writes( " )instead of( @ ) and vice versa when I write Shift '

Are you sure you don't have an alteranative keybord map enabled? Not every keyboard type has the keys mapped the same way. And it's the software that tells it what kind you have, not the actual keyboard.

How do I check??

Which Operating system are you using? Windows XP? WIndows 7 or something else?