I recently downloaded the demo to give the game a try and unzipped it to the desktop. when i go to run the game it takes me to a window asking me to select a program to open it. I am using Windows Vista and the hardware is up to specs. Is there anything i am doing wrong or can do to make it work?

For the record, this is the forum for the Mac version. You may want to go to the Introversion forums for help.

Actually, I wonder now... did you download Defcon from this website?

If you downloaded DEFCON from Ambrosia Software (i.e. this website), then you downloaded only the Mac version. The Windows version is located at http://everybody-dies.com (click the demo link on the right). For support, your best bet will be to visit the Introversion Forums (Introversion Software is the company that created DEFCON -- Ambrosia helped port it to the Mac, and publishes the Mac version, but they are not the originators), and try to get help there. And don't be hugely surprised if the Windows version of DEFCON does not get along well with Vista -- DEFCON uses OpenGL, and many video cards do not yet support OpenGL under Vista. Things have improved significantly, but are not perfect yet. So, download the demo from Introversion, and see how it goes.

xander