You just need to fill in the selection boxes.
The first one, you will select "wireless"
In the next you will choose which wireless adaptor you are using
In the next you'll choose "driver"
And finally you''l need to tell it whether you are running the 32 or 64 bit version of windows.
Finally you click the red download now button.
As i don't know which version of windows you have, or which wireless network adaptor, I can't give you any more help than that - but it is quite straightforward.