Size: Bigger isn't necessarily better. For a given resolution a larger LCD creates a larger image, but will have a looser pixel pitch. All things being equal, smaller LCD screens, for a given resolution, will produce better image quality because of its tighter pixel pitch. Smaller LCD screen sizes generally come with a lower price as well.
Pixel response time: Faster response time eliminates streaking and ghosting. Looks for a response time of 30 milliseconds or faster (lower).
Viewing angle: LCD monitors have limited viewing angle as compared to a CRT. Look for both wide horizontal and vertical viewing angle specifications. Look for a 160 degree viewing angle or wider.
Contrast ratio: Is the ratio of light intensity between the brightest white that can be produced and the darkest black that can be produced. Contrast ratio is a major determinant of picture quality. The eye sees contrast as an important element of overall sharpness. Look for a 400 to 1 contrast ratio or better.
Refresh rate: LCD?s do not suffer from flicker like CRT monitors. Running an LCD at a low refresh rate will produce a flicker free stable image and this is not a specification you have to worry about.
Power Consumption: LCD monitors typically consume approximately half the power of a CRT monitor. Does power consumption justify the added cost of a LCD? Not really, using the assumptions below it will take over ten years for the lower power consumption of an LCD monitor to compensate for its higher price.