How do I get the best picture on my TV, when running ex. DivX from PC.

I have a GeForceFX 5700 Ultra with a NVxx (nVidia tv-out-chip)

connected to my

Philips 32PW9509

with S-Video cable.

But i'm not satisfied with the quality on the tv

What should I set of settings on pc, and witch settings are best on tv ?

Does FFDshow have anything that can make the pic better than org. Divx/XviD-decoder ?

The picture on tv is also lagging - why?

Thanks !