Multiple Monitors and Productivity

I am trying to run a multiple monitor setup, but I wanted to know if you need to similar monitors to do this. I have a 19" monitor connected and a 23" TV connected by S-video. I can switch between each screen, but can only use one at a time. I have an ATI X1300 graphics card and Windows Media Center Edition. The card has a primary and secondary drive on it, but when I enable the second monitor it flashes and dose nothing. The card came with a control center but that is unable to setup second monitor either, and I out of luck here?