Refresh rate on TFT doesnt compare to CRT. CRT's are drawn by a scanning beam of electrons which activates pixels 1 at a time, if you photograph a CRT with a 1000th of a second shutter speed camera, you'll see just a fraction of the screen is actually lit. The faster the refresh, the more of the screen is lit in any one split second, and the more the brain is fooled. >70hz is generally sufficient to fool the brain.
On the other hand TFT screens are 'fixed' you could have a 1hz refresh rate on a TFT and it still wouldnt flicker. All the pixels are charged, and change gracefully from one image to the next. There is no 'scanning'
TFT's are often set too bright, so worth adjusting them, they are normally setup for use in a brightly lit room. If you sit in near darkness then they would be far to bright and that could cause headaches. Turn down the brightness if you use the computer in poor lighting etc.
TFT's can get tearing if the graphics card sends out too many frames/second. Best to enable Vsync on the GPU. This limits the maximum framerate to match the GPU. The more important minimum frame rate is rately affected much. Tripple buffering can help to keep any affects on minimum frame rates to a minimum.
Viewsonic screens (and no doubt some others) do actually allow a 75hz refresh, so thats an extra 15fps on those screens.
