Use PC as HDTV

Me again....with yet another PC/HDTV hybrid question. :D

I want to set up my PC as a backup HDTV and also occasionally record a TV program with the PC instead of buying a DVR or paying Comcast for some service.

Questions:

1. What sort of card or device will I need for the computer? Suggestions welcome (mid-range price)

2. Special software needed other than the usual card drivers? (Running Win7)

3. My current TV requires I use the Comcast HD converter box. Will the card I buy for the PC require a converter box of it's own, or does the TV card perform that converter function?

4. The cable configuration in my house is.....street to splitter. From the splitter, one line to second splitter for all TVs in the house. Another line from first splitter to modem, then router. Does it matter where I tap in with another cable for this PC/HDTV setup?

Thanks

Mods....if this question is too much TV and not enough PC, feel free to move me to the proper place. :)

1) You basically just need a Tuner card. I can recommend Hauppauge or Terratec as excellent brands, but obviously not specific models, as it's all different over there. I know Hauppauige at least do different cards for broadcast signal, satellite, or cable.

2) As long as you have Home Premium, Professional or Ultimate then you don't need any extra software, the excellent Media Centre has everything :)

3) Not sure about that

4) It doesn't matter at all.

3. I'm pretty sure the TV card will be limited on the TV channels you can get. You'd need a Comcast converter box to get the Premium channels.

If your ComCast converter box uses a CableCard, you may be able to get a tuner that uses one.

Thanks for the replies. :)