Enable the global terminal colors in Mac Mountain Lion

Simply add the following two line to ".profile"

export CLICOLOR=1

export LSCOLORS=GxFxCxDxBxegedabagaced

CLICOLOR=1 simply enables coloring of your terminal.

LSCOLORS=... specifies how to color specific items.

"Emacs basics: Changing the background color" by Sacha Chua

From: http://sachachua.com/blog/2009/01/emacs-basics-changing-the-background-color/

To change the background color and other attributes, use the command M-x customize-face, and specify default as the face to customize. Change the attributes and the sample text will reflect your settings. When you are satisfied, select Save for future sessions. Your changes will be saved to ~/.emacs and reloaded the next time you start the editor.