I normally use Microsoft Snipping Tool for screen shots.
I posted how to make a "hot key" for Snipping Tool back in February:
http://www.thechipboard.com/archives/archives.pl/bid/399/md/read/id/1329085/sbj/snipping-tool-hot-key/

I had Windows 7 Ultimate at the time.
I have Windows 10 now and Snipping Tool is still here.

Now I have Snipping Tool pinned to Start in Windows 10:

Try playing with it, it's fun!