it has nothing to do with the operating system, its all about the quality of your screen, your video cards and your video drivers.
1. buy a good LCD monitor
2. set it at the resolution it is optimized for.
3. you picture is now as clear as possible.
(sometimes they look crappy if you set them at a lower resolution, which could make it hard to read, but say you have a 19" monitor and its optimzed for 1280, then you should use it at 1280. thats what i have and it looks shitty any lower.)