I have a Compaq Presario, Windows XP and the @ sign has switched places with the " key on my keyboard.
Tried a different keyboard with the same resulst.
Any suggestions on how to get my keyboard back to normal?

control panel | regional & language options

make sure the settings are right for you.

this is usually a confusion between US & UK settings.

If that does not resolve the problem there is an option in bios. (press the delete button when windows starts loading)

Thank you, Jaynee.
I will give both a try.
I appreciate your suggestions