I install the free Gadwin Print Screen
http://www.gadwin.com/printscreen/ on computers I build. It is reliable, free, and has great functionality being able to capture to a file in many formats, send to printer, and more. I set it up to capture the entire screen using the Print Screen key.
I also use Snagit on my system, but Gadwin has many of the same options.
People like the price, and being able to capture screens. I like the copy of error messages when I get a call that something is wrong on their system.