Probably one of the best features of Windows XP was the introduction of ClearType display. Enabled by default on Vista but it needs to be enabled and configured on Windows XP. 

With Windows XP, ClearType delivers improved font display quality over traditional forms of font smoothing or anti-aliasing. ClearType improves readability on color LCD displays with a digital interface, such as those in laptops and high-quality flat panel displays. Readability on CRT screens can also be somewhat improved.

I found a very useful free application (from Microsoft) called ClearType Tuner. It enables and configures ClearType display on your Windows XP system. If you are thinking how to do that, worry not, as there is also an online application ClearType Tuner Setup which will do all the job for you. I found the tool to be very easy to use and helpful.

The best thing about the tool is that it will configure ClearType so that it looks pleasing to the eye and according to your own preferences rather then making your display a bit blurry. If configured correctly, you will find the display a lot better then before.