In order to add commentary to a fast moving video I've been pausing the frame by taking a snapshot, saving to a file, recording narration, saving to a file, then manually adjusting the snapshot time. But the process feels clumsy in Windows Movie Maker. That software is also no longer supported by Microsoft.
Ideally I'd prefer to use a simple GUI editor like Movie Maker (ideally with keyboard shortcuts and/or voice control) since I don't have a lot of free time to master an advanced tool. Though if more involved tools are the only way to streamline the process then please share your experience.