Regarding the @ symbol;
Missing @ Symbol
Normally this is a result of having a system set up for the US and not UK
Workaround solution: (1)
( Press and hold Shift + 2 ) should give = @
Changing your system keyboard configuration to uk in XP
Click Start / Control Panel / Switch to Classic View - click regional and language settings - looks like a globe
Select the region that you want then click on advanced - ensure there is a tick in the very bottom box that apples it to every user and default user setting.
Now goto the languages tab - select the region that you want - then click on the add button.
In the little box if you have another region in there as well - select it then click on the remove button.
Now click apply and then ok - then restart your pc - that should sort that out for you.
This is assuming you have Windows XP Home/Professional.
If you have the drivers and utilities disc,install everything on it.
If you dont,please post the motherboard make and model number and we can find your sound driver.
A common sound driver is the realtec ac97 but this is not to say this is yours (only a guess at the moment ) click here