Assuming you have XP, on your toolbar there should be a box with a question mark in it. On the right of that box there is an arrow pointing down, click that then click settings. Click Add, then add English (United Kingdom) then click US and click remove. Click OK then I think the next time you reboot it should be fine.
Change the keyboard to british UK i suspect it is set to US keyboard,open control panel select date/time/launguage and then click regional and launguage on the box that opens select English UK in the drop down box.