REGARDING THE TV TUNER PART OF THE QUESTION
Just wanted to say most of the computer tuners only work with a direct connection from an over the air antenna or direct connection from a cable (not satellite) from a wall, not via cable or satellite signal scrambler / set top box, and they only let you watch / record free/network channels such as CBS, NBC, PBS etc.
They are VERY few tuner cards that allow you to tune into subscription channels such as MTV, but those tuners need to be fitted with cable cards from cable companies plus most of those tuners are only available on OEM computers (such as HP and Dell computers). There was a rumor a few months ago that tuners that can work with cable cards were made available to system builders that were not OEM manufacturers, but I am not sure where it went after that. I HIGHLY doubt there's something for SATELLITE.
If you want to watch and record all TV channels you get via your satellite subscription, one device that may work is Hauppauge's HD-PVR. This is NOT a "tuner". It is a "video capture device" and therefore, even if you have two tuners on your satellite box, whichever channel that you are watching will be the only one you can record as that is the picture your satellite box is outputting. You hook up the component output of your satellite box to this device and use an included software to watch and record. You may or may not have to unplug HDMI for your television from your satellite box in order to allow the satellite box to output through the component to this device when you watch TV on your computer.
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