Re: s video
I'm a bit confused... Do you mean you got a stand alone unit or one for your computer?
Assuming you meant for your computer... S-Video is the highest quality most computers will export. If your TV has this port, you should get pretty decent quality from it. If not, you can use an S-Video to RCA converter(or even make one) without too much of a drop in quality.
There's also component video, but I don't think any computers export that right now... Some might have converters, but I don't know if the quality is any better...
One note, video on a TV from a computer will look quite blurry when compared to a stand alone DVD player. Why? Resolutions. TVs run at something like 720x480 where as computers run at much higher resolutions for the most part. Then, a computer screen is not interlaced like a TV, and the video card has to compensate for that. IE, loss of quality...