Graphics Advice on home PC for front end and entertainment.

Well I want to make my living room high tech and easy to use. So I want to integrate everything to a front end. Got everything and only one thing tv. How would I go about getting digital cable to show up on my pc? Is there a card I can use with remote use or anything of that sort? also it has to be good to support a 40 in hdtv monitor. so i have an sli set up right now. so the way I want it to work would be like so

going in tv card or whatever u guys recommend
going out to tv-from one of the video cards

any ideas