Err, no none of the above....

You need to feed a cable directly from the aerial on the roof into the TV. Not a cable from the Sky dish, but a cable from the AERIAL.

Then, depending on the spec of the TV, you will either have an analogue tuner and a digital tuner, or just a digital tuner. If both, you will have to select the digital tuner, like Lee said. My Sony is like this - analogue and digital tuners, button on the remote to switch between the two.

For ease of setting it up, I suggest you disconnect the Sky feed from it, as it isn't doing you any favours right about now....