I think you will find there is no distortion as the image will be presented in the 4-3 ratio. If however you increase the viewing size of the image to fill the screen you will not be able to see all of it. i.e. an image in portrait viewed to fill the screen top to bottom would not fill the screen at the sides.
I use a TFT 1280 X 1024 for all my photographic work, which accounts for 90% of my PC usage.