High Contrast heightens the color contrast of some text and images on your computer screen, making those items more distinct and easier to identify.
Open the Make the computer easier to see page by clicking the Start button , clicking Control Panel, clicking Ease of Access, clicking Ease of Access Center, and then clicking Make the computer easier to see.
Under High Contrast, click Choose a High Contrast color scheme.
In the Appearance Settings dialog box, under Color Scheme, choose the High Contrast color scheme you want, and then click OK.
To use a keyboard to turn High Contrast on or off, select the Turn on High Contrast when left ALT + left SHIFT + PRINT SCREEN is pressed check box.