Went to an e-mail there and I have noticed tonight that the @ symbol does not work as it should e.g if i press shift + the @ sign I get " and if I press " (i.e above the 2 + shift), I get @. (I hope that makes sense)
Sounds like you have your keyboard set to US layout by accident. You can swap it back by [assuming you're using windows XP] going to Control Panel > Regional and Language Options > Languages tab > Details button, then click Add, pick English [United Kingdom] from the first box and also United Kingdom from the second box.
You should now be able to select the US keyboard and remove it :) hope those are right, you'll get the general idea anyway I think.