I don't know about the computer settings.

But look on the back of the tv and see how the s-video jacks are labled. Probably Video 1, 2, or 3. Should be directly about the yellow, red, white composite a/v inputs.

Simply plug the s-video cable into that jack, select that input on your tv, and it should work.

Make sure that whichever tv input is chosen that you don't also have a yellow video cable plugged into the same numbered input jack.

You're not feeding an antenna signal to your TV, so you don't need Ant1 or Ant2. Video1/2/3 are all the same; there's just three of them. Colorstream HD1/2 are, I would guess, high-definition inputs (which your Dell most likely is not). DVI, at least in my experience, is only for computer monitors (for example, if you were to connect a bigger external monitor to your laptop). I'm guessing (without having seen either the laptop or the TV) that you want Video 1, 2, or 3, and then will have to make the same choice on the front of the TV (or the remote).

I'm not sure if Dell switches around some keys, but on my IBM ThinkPad and my Apple PowerBook, fn (Function) and F7 are the keys to press to get laptop and/or external display working. Find the icon that looks like one rectangle on top of another.