S-video is out of the question.
the VGA typically maxes out at either 1366x768 or 1400x1050 (or whatever the size is) so for a tv that is native 1366x768 like the vizio it works fine. For a tv like my parents 1080p sony, it won't upscale for you, while the component will, so your stuck with black bars somewhere.
In terms of better signal quality, i don't know, but i'm leaning towards Component.