There is a very nice feature in Windows.... Well actually there are quite a few (bad ones)
If you go into the language section of the control panel you should make certain that you only have english language and the actual keyboard that you're using. Remove any other language/keyboard settings.
The thing is that there is some kind of weird shortcut to switch keyboard setup in windows, and this is enabled by default, Nice
This thing is so crappy in Windows that it's just unbelievable......
Wonder why I'm running Linux
I can't provide you all the details on this Dave (because I have Linux here now, try it!!!), but if you like I could dig into this deep and show you exactly what to do..... to make sure that this doesn't happen again.....
(I'm an MCSE certified Microsoft engineer)
If I should provide you assistance I would need to know exactly which windows version you are using.....
You can find out by choosing run, and the command: winver