Another Newbee!!

Hi there, another newbee to all this and I was wondering if anyone can help me out with these problems I’m having.

I currently have a BenQ W100 Projector set up in my house, I have an S-Video cable running from this, through the floor boards and down the wall to my TV point.
From there my tv provider only uses Scart connections so I have a basic s-video to scart adapter and this does a job for the tv but when I watch football the picture isn’t very crisp at all, I was wondering if there is any other kind of adaptor / connection I could use, without lifting the floors and replacing the s-video wire, which would give me a sharper picture??

Also, I’m thinking of purchasing a PS3 for that room but being totally useless with this sort of thing I wouldn’t have a clue where to start to get the thing connected up. Could anyone tell me, in layman's terms, the best and easiest way to connect a ps3 up to the projector, preferably using the s-video cable already installed in the room??

Any help would be greatly appreciated!