You need to get to the keyboard options in the Control Panel to tell you what your keyboard is.
I cannot currently descibe the way to the keyboard options as I am in linux, maybe someone else can.
[UNRELATED] Also, I get this all the time in Garry's mod, no idea why, its fine for 5 mins then just goes wierd.
sorry but can't find a language tab anywhere, it just goes on about the drivers in the keyboard or something and when it was made etc.
edit: could it be that i dont have the correct font in the fonts folder in control panel?
there is everything in the control panel except for a language option. =P
edit: omg i looked at the pic i uploaded and it was right in front of me.
it says English (United Kingdom)