Taking a screenshot

I have a computer monitor that has both the computer's VGA cable connected to it aswell as my Xbox 360's component cables connected to it. What I'd like to know is if there is any way to take a screenshot of what's on my screen when I'm playing Xbox 360 without the need to buy any software or anything.

I really can't get enough of all this RedCream worship.  Please pay more attention to me.  I win either way; I'm living a life of TOTAL WIN.