Many of the fonts and colors and used by eclipse components can be set using the General > Appearance > Colors and Fonts preference page.
A tree is used to navigate among and show a short preview of the various colors and fonts. The current face (but not size) of any font is previewed in its label. Colors are previewed in the icon associated with its label. Additionally, some categories (Workbench in particular) provide a more detailed preview of their contributions. This preview is shown below the description area if available.
Font settings can be changed either by selecting the font from the list and clicking Use System Font to choose the Operating System font setting or by clicking Change to open up a font selection dialog. Reset can be used to return to the default value.
Color settings can be changed by clicking color to the right of the tree area when a color is selected. Reset can be used to return to the default value.
Here is what the Colors and Fonts preference page looks like:
The Colors and Fonts text field can be used to filter the contents. Simply type in an entry and any matching results will remain in the tree view.
Descriptions and previews are provided when the Workbench colors and font settings are selected.