Click on one of the links in ChuckFicken's post, above. (i.e. choose the right one depending upon whether you're using Windows XP or Vista).
You should see a box asking you whether you want to open the file or to save it. Select 'Save' and click 'OK'. You'll then see a box asking you where you want to save the file to. That can be to anywhere you like but, for simplicity, I suggest putting it on your desktop. (Click the little downward-pointing arrow at the right of the box which is labelled 'Save in'. Click on 'Desktop', then on 'Save').
Then close (or minimise) your browser window, so that you can now see your desktop. You should see a new icon with a zip down the middle of it. From there, follow the instructions in my previous post. (After you've installed the driver you can delete the icon from your desktop).
Chris