Problem using HDTV as 2nd Monitor

I have a 24 inch Samsung LCD Monitor at 1920x1200 that I am using as my main monitor and a 42 inch Philips plasma TV at 1080i that I am trying to use as a second monitor to watch movies and shows I have on my hard drive while I work. Both displays are connected to my video card (evga 9800 GTX+). The TV is connected with a DVI to HDMI cable (the HDMI is in the TV). I successfully set both monitors up using the nvidia control panel at their correct resolutions, but for some reason on the TV part of the picture is cut out (I cannot see the top, bottom or side edges of the picture). I tried messing around with the nvidia control panel features and the closest thing i found to correct this issue was changing the resolution of the TV to some off the wall amount which I would like to avoid. I tried using the TV's menu with absolutely no success, there isn't even an option for what I am trying to do. I would really like to fix this issue and any help you could offer is greatly appreciated, thanks!