does s-video really make the picture better when watching dvd's?

[kakomu]

the difference is that RCA and Coax are both analog, whereas S-Video is digital. This basically means that with RCA, the picture can degrade on the way from the source (and more often than not, does with old, long or dirty cables). The difference isn't going to be night and day, however, a little grain may clear up. As for the difference between regular and super thick, premium, gold-coated cables, it won't be really noticeable (if at all). Stick with the regular cables, and look online for the gold plated wires if you're really concerned about it.

(just checked online. Professional audio studios use mega-gold plated cables only to maintain as low amount of signal degredation as possible. Any home user wouldn't notice the extra fidelity. So, no need for ultra-expansive cables).