Mac OS X 10.6: If screen text looks blurry or jagged
If the fonts on your screen look fuzzy, blurry, or jagged, you may want to adjust the font smoothing style or change the size at which fonts are smoothed.
To smooth the fonts on your screen:
Choose Apple menu > System Preferences and click Appearance.
In the bottom section of Appearance preferences, choose font options.
Use LCD font smoothing when available: LCD font smoothing makes fonts appear smoother by reducing jagged edges, but some people find text appears blurry when font smoothing is turned on. Select this option if you want LCD font smoothing to be used in applications that support it. If you’re not sure which setting you prefer, try reading text on your screen with and without LCD font smoothing, and then choose a setting.
Turn off text smoothing for font sizes: When smoothing (or “antialiasing”) is on, smaller fonts can be harder to read. If you plan to use small font sizes in your documents, choose a font size from the pop-up menu.