Could you post a screen shot of what you mean, and maybe a screenshot of your settings?
The Quickcam 4000 as a model is pretty old and has been out of production for a couple of years; the webcam you have has probably deteriorated during the last couple of years. This adds to the problem of graininess.
On top of that, what is your lighting setup? Sometimes when I set up my lighting, it feels like there is a lot of light, but then when I turn on my webcam it turns out that the lamps are way too far away (or otherwise simply too dim) to provide the amount of lighting needed.