While many users like the default look of the Ubuntu desktop, part of the fun of using Linux is its infinite customizability. This tip illustrates how to navigate the Gnome Desktop configuration to change the colors use by your applications.
As of the 7.10 Gutsy Gibbon release, most of the Gnome Desktop's appearance settings are consolidate in the "Appearance Preferences" utility. This can be accessed through the main system menu System > Preferences > Appearance
Once the window appears, click on the Theme tab. Then click the Customize button. A new window with the title Customize Theme will appear. By navigating to the Colors tab in this new window, the colors for the currently selected theme can be adjusted.
Note, however, that only some themes allow for color adjustments. Unfortunately the default Ubuntu theme, "Human" does not allow for color adjustments. To change the theme, click the Controls ("controls" are a programming term that refers to various elements of your desktop windows like menus, scrollbars, and buttons) tab, and choose an entry that allows for color adjustments. A popular one is the "Clearlooks" theme. After the theme has been selected, return to the Colors tab, and the various color buttons should no longer be grayed out.
Also, note that the "Background" color for "Selected Items" is also used throughout your deskop, for example, the window titles, and the scrollbars.