Copy the video to your PC.
Install an OLD version of VLC Media Player onto your PC. (There have been some problems with video editing in the recent versions). I use v2.0.3, which was designed for Window 7 & 8 but I'm fairly sure that it will still run in Windows 10:
http://www.oldapps.com/VLC_Player.php?old_vlc=7998
Open VLC.
Go to the View menu and select Advanced controls.
Play your video. (Use the Media menu)
At the point where you want your clip to start, click the red 'Record' button.
At the point where you want it to end, click the 'Record' button again (or use the black Stop button).
You'll then have a copy of the relevant section of the video in your computer's 'Videos' library.
To take a snapshot, start as above but, at the point where you want to capture the image, click on the 'Snapshot' button (immediately to the right of the 'Record' button). A snapshot will then be saved to your 'Pictures' library. Note though that:
(a) the human eye puts together a clear moving picture from the individual frames of a video, even though some of those frames might be rather 'fuzzy'. So you could capture a fuzzy image. (If you do, try again. A frame which is a fraction of a second to one side of the first one might be far clearer) ; and
(b) The default image format used by VLC is .png. You'll probably want to change it to .jpg
before capturing an image. To do so, go to Tools > Video > Preferences.