Update 2022: This software no longer exists now. We recommend you to try some other alternative instead.
Video2Thumbnail is a free software to create thumbnail from video. It can extract images from video. What I really liked about this software is that it is extremely simple to use, and does not comes with tons of options.
To create thumbnail from your video, you open this software, select that video you want to work with, and play the video till the point you want, and then extract image of any particular frame. When you extract image from your video, you can store it in your chosen file.
Unlike other software that we reviewed earlier (ImageGrab), Video2Thumbnail does not comes with flashy options like extracting multiple images from video together, but its simplicity of use make it a good video thumbnail software for home users.