I think the default key is F11, at least thats the one for RTCW. The screenshot is a .tga file though and usually pretty large. Once you take the screenshot you're better off converting it to a jpg, that would lower the size quite a bit and help with loading it in the forums.
Just checked the RTCW key for screenshots is F11, and any date for australia has yet to be proven. So, your dates are as good as his...when sat. rolls around we'll see if his is true, and the same for yours on monday.