Powerful tool but far from the easiest to use. I use this for basic manipulation, have patience and search for tutorials on anything you looking to do using the tool.
Greenshot is a light-weight screenshot software tool for Windows with the following key features:
Allows you to record your desktop to video. Tip, when you need to present a demo pre-record it using this software then if your demo goes wrong (live) then just playback the video OR if somebody asks if we can go back 🙂
The nice thing is that you pause/rewind etc to explain certain points.
Use for basic editing of audio files, seems very popular and has multiple platform support and is open source. It records/edits etc.