if you use a TV tuner card, you will have to keep your computer running as well and any activity on the computer will interfere with your gaming experience.
Try a Dany TV device, you should get it for Rs. 1000 to 1200/- I use it with my LCD with a PS2 to avoid depriving everbody else of watching TV and did not see a point in buying a separate TV. Although I had a ATI VIVO and a Zoltrix TV card in my PC but this device is much better in terms of convinience.