Windows Vista - Playing Games using the arrow keys

Its been a few months now but my arrow keys stopped working whilst playing games i,e when I use the arrow down key or up key it moves the internet page up or down this is driving us all crazy so far we have tried pressing the 
 FN keys on its own,
FN key with a F numbered key eg FN and F11 which is also the scr lock key
just the Fnumbered keys on thier own
but still the problems persist we just can't seem to figure this out we just want to play our games without moving the page up and down can any one help
we have Microsoft Windows Vista
thanks for taking the time to read our problems and hope someone out there can help

I would suggest you few things which will be helpful

 Try to Upgrade DirectX which is also important for mouse/keyboard interface

and as you said you were able to browse pages with arrow keys perhaps the game you are playing needs some addional plugins flash or java

also check with keyboard drivers

Hope this helps you