I have been using MWSnap for a long time. It is generally considered one of the best free screen capture tools.
There are a surprising number of comments like the one below at the MWSnap forum.
Thu Jan 15, 2004 5:51 pm : MWSNAP is GREAT!
Thank you for offering this software for free. It is extremenly useful in many ways. It is easy to use and does a great job capturing what I need. Before this I used to work between MS Paint and Windows Print Screen. This saves me alot of time and effort!
I would love to make a donation to show my gratitude.