I am not sure about Windows 10 (I haven't migrated yet), but in Windows 7 there is a little known/little used tool included in all installations called the "Problem Steps Recorder." You can get to this tool by clicking on the start button and typing 'psr' into the search box.
The tool itself is pretty clunky. When you open it you see a toolbox - you have to click on the drop-down on the far right > Settings and pre-configure the tool before using.
In the settings you need to enter the location to a new zip file, enable screen captures, and then I always update the number of captures to 100.
Click Ok > and then on the main toolbar click "Start Recording"
Once it is configured you can click Start Recording and it captures both a screenshot and an action label for every action a user tables while it is running.
When you click stop recording the zip file you specified in the settings is created and inside of the zip you will find a mht. The result is pretty awesome - Each step is outlined and you get a screencapture with affected button/drop-down highlighted. Here is a small example:
Unfortunately, PSR lacks some of the great features available in SnagIt -like the option to select a region (or even just a single monitor!)
For those of us who work in an organization that supports end users - having this type of feature to create a step by step 'this is what I did' type story image would be very powerful.
Right now I can use snagit to grab all of the screenshots, but I cannot automate screen captures based on action or capture the action in text. I would like to recommend adding a PSR like function to snagit to bridge the gap between single image and full video.
Please let me know if you would like any additional information.