The rules are different for screen shots.
We have talked about avoiding compression when printing screen shots. There is still something we should pay attention to. Don’t resize your screen captures in your image editing software. This goes against everything you've probably ever heard about image editing. In most cases it is best to get your image to the correct dimensions from the screen capture software before placing it in a page layout program. Here's the exception to the rule. With screen shots you can often get better results if you resize it (smaller!) directly in your page layout program.
But don't rely on what you see on your screen. The one that looks best on the monitor may not be the one that prints best. Make a copy of your screen capture and print a version resized in your image editing software and a version resized in your page layout program to find what works best for you. This can change depending on the amount of resizing.