You must download the .zip file and then unzip the file using a utility such a

- winzip
- winrar
- 7zip.

WinZip has a free 30 day trial you can download: http://www.winzip.com/prod_down.htm

WinRAR has a free 40 day trial you can download: http://download.cnet.com/WinRAR-32-bit/3000-2250_4-10007677.html

7Zip is a free (GNU LGPL license) program you can download: http://www.7-zip.org/