Using TV as second monitor problems

Graphics Card: BFG 7800GTX OC
Monitor 1: Samsung 713N 17 inch LCD
TV: Samsung 32 inch CRT (HD ready)

I've connected the graphics card to the tv by using the s-video slot on my graphics card so that it works like this:

Graphics card (s video) -> Converter (for the red, blue and green plugs) -> TV

When I load up the pc the colours seem to work fine (a bit out of resolution but it's ok for now), however, once i get into windows it's all blueish, like the red and green are barely if being used at all. Now, I know it must work because the windows logo comes up fine. There's also nothing wrong with the tv because normal tv works just fine on it.

As for the resolution, how do i set it so that it is hi def? I've updated all my drivers for nvidia.

I'm completely lost here and close to tears

Please help,

Thanks in advance

EDIT: Ok I've got the colours working - apparently i can't choose 720p or 1080i right off the bat... even though my tv DOES support those

http://www.samsung.com/au/products [...] 2z30he.asp

That's the TV i have, so if any of you guys have any ideas I'd be happy to hear them

Thanks