https://www.movavi.com/ You could also use Ninjatrader Market Replay. I journal with Movavi but the size of the files adds up fast so I only retain important recordings in the cloud. Market replay is always available and doesn't clog up your computer.
Use the "PrtScr" button on your keyboard. Different operating systems use it differently. In most Linux distros, just hitting PrtScr (print screen) takes a screenshot of the whole screen. Alt + PrtScr saves only the open window. Shift + PrtScr lets you click and drag an area to save. Probably works the same in WinDOHs and I know they used to have screen capture functionality at one time. Google "PrtScr key". For video capture of screen activity, I use Kazam. Open source of course. Not sure if they have a windows version but I bet they do. It even works for saving movies that you can stream but not download because it simply saves the screen and speaker outputs and combines them into mkv.
Debut Video Capture is good software too Http://Www.nchsoftware.com/capture/index.html It costs for the full version.