Only thing is I know a little more.
There are 2 ways for TV on a computer well 3 but the main two are either a high end AGP Graphics card with a Tuner Built in like a Hercules 3D Prophet All-in-wonder 9000 Pro (Around £200 mark)
Or a seprate but cheaper route one of the Hauppauge WinTV PCI say model 747 which has Nicam, FM, Text & remote. (£72 ish)
I am now trying to find out how the card puts the picture onto the acutall monitor. Is this done by a link cable if using a Hauppague card to the AGP graphics card or does it channel its data through the actual PCI slot to come with a pic on the Screen.
The better quality the AGP card I expect will also make a difference, and also processing power & memory.