First, make sure that you've installed the driver for your graphics card. Secondly, make sure that your graphics is set to the native resolution for your monitor (the optimal resolution it can handle).
Thirdly, ensure that your monitor is set correctly. If your monitor has an Auto Adjust
feature (like the majority of LCD TFT monitors), then use it to re-adjust your display to the optimal settings.
Lastly, it may be the font smoothing method causing the apparant blurr. Try changing the font smoothing method by going to Display Properties > Appearance Tab > Click Effects button > Change the font smoothing method used at the top
. As well changing the font smoothing method, you could try disabling font smoothing to see if it looks better.
There are clearer instructions on changing and disabling font smoothing in the following article: Changing Font Smoothing Settings in Windows XP