Welcome to WebmasterWorld Guest from 188.8.131.52
I think that most people have no design sense and as long as the site is clean and easy to read, has what they came for, they will stay.
There is more but I can't remember them all. I do know that on average MALE visitors prefer solid dark colours like Blue, Black, Green... while FEMALES prefer pastel colours and lighter shades of the above.
Play with the colours until you figure out what works for you.