Rani, welcome to Tom's Hardware Forums!
In Control Panel, set the display screen resolution to the native resolution of the monitor.
The fonts and characters may be too small at this setting. To correct this, adjust the DPI (increase or decrease) until the fonts are of the right size for you.
Details here: http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/display_change_screen_resolution.mspx?mfr=true