I have never used dream weaver. Have are you sure that the style sheet is being included properly. Are you sure you are using proper hexadecimal values? Did you forget the "#". If you still can't figure it out then create a new project with a css file and a single div and see if you can aply the color to that.
If you are still banging your head against a wall then maybe you should upload some of your code so that we can help you better.
and thou shall not dual boot for ye can only serve one OS.
Just to be clear Linux is a Kernel not an operating system.