Setting Primary Display on a Windows Laptop

Hi,

I really have no idea where to post this as all the threads are Mac based.

My friend just got a TV/Display that he has connected to his computer and wants to watch DVD's and use as a second monitor.

He asked me to help him set his laptop's screen as the secondary display (and, being a Mac user, I couldn't figure it out). I was wondering if there is anyway you can do this.

It seems like this would be really simple on a Mac, but I couldn't figure it out on Windows.

The only thing I tried was right clicking the desktop, and going to display properties, and then trying to right click the primary monitor icon and switching it to secondary (the option was grayed out).

Thanks in advance for your help.