If you like working with a dark background and enjoy syntax highlighting but hate the navy blue on black, try putting the following line in your ~/.vimrc:

set background=dark

If you're on a dark background terminal, the hightlighting after searching in vim can be maddening. To turn it off for the session, type :set nohls.

You can change your X background color with this command:

$ xsetroot -solid steelblue &

The setting is not persistent; the command should go in ~/.xinitrc or ~/.Xsession, depending on how you start X, so it will get run each time X starts. The color definitions are in the rgb.txt included with your X distribution.