As the above say, it sounds like a US/UK keyboard issue which makes the fact that you say you have 'changed it' puzzling!
The @ and " characters are transposed, tho; the primary keys, i.e. the 2 and the ' are correct
It sounds as if you actually
have a US keyboard (see below) rather than a 'US' setting in Windows. Where did you 'buy' it? I reckon you need the 'US' keyboard setting in Control Panel if that is your key layout.
Tutorial: Remapping a US Keyboard in the UK (Windows) « Andy's Ramblings
You did not say which OS, though! W7?