It sounds very much like you have one of two problems.
A) You have "sticky keys" or "single shift" enabled, or as suggested above Function is set to on, this is unlikely as you would need to set sticky keys on, then set function.
Sticky Keys lets you press single keys in sucessions where you would normally use multiple keys at once, like for a " you would press Shift and 2 together. With sticky keys you can press shift on its own, then 2, within a set time and will stil get the 2.
Single Shift allows you to use the shift button as the caps lock button, so even though Caps Lock is turned off, pressing shift will turn capslock on.
Both these options are found in "Control Panel>Accessibility Options>Sticky Keys"
Turn them all off (or just unselect "Use Sticky Keys"
B) You have your keyboard region on windows set to the American Standard and have a british keyboard, or visa versa.
This is set in "Control Panel>Region and Language Options>Language>Details" and select the proper keyboard as your default, You may aswell, delete the instance of the other languages, as common language keyboard layouts can beinstalled just as easily, and dont need the windows CD to do it.
Hope this helps.
Regards
NC
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