I had originally designed my website with a red background and orange letters, which looked really great. But after looking at it so many times I realized it made me very tense, so I changed it to blue and white with black letters. Not nearly as exciting, but much more soothing. I certainly don't want my prospective clients being tense.
Here is a link to an article on the psychology of color in marketing. I think it makes sense to see what the colors on your website convey. I didn't know red made people hurry to leave. Now I do and am glad I changed my color scheme. It now conveys trustworthiness, honesty, youth, sophistication, and elegance.
http://www.nightcats.com/samples/colour.html