Ok I make an image n CS and I use the eye dropper tool to get the Bg color so it can match in my xanga but when I put the color in my xanga as my BG the image always look darker ..and I wonder why is it the type of file I save it as or the host..i saved it in JPEg and PNG and I used to ddifferent hosts and its still the same...

You should use the eye dropper tool on the image when it's been saved as a .jpg.. and if you should also save the images as only one type of file, not two different types.