But I've never had reason, before, to do video screencaps. Turns out VLC has it built in, so I feel extra-foolish as I've been using VLC for approximately forever. Here's an 8× speed copy of my very firstest hamfisted attempt.
So it's a start. Obviously, it'll need more things, like (A) more steps (B) a voiceover explaining what I'm doing and why, and probably (C) a track of me humming yakety sax for music. I should probably also hide the Windows taskbar; it's kind of dorky down there. And I guess maybe (D) a title-card or somesuch.
But it's nice to know the actual screen-recording part is super easy. Thank you, VLC. I already knew you were handy, and I feel bad for not knowing about this bonus awesome, but just as necessity is the mother of invention, I guess it's also the midwife of feature discovery.
If there's some aspect of my graphicky things you'd be interested in seeing videos of, my inbox is always open, and in the meantime I'll probably do some basic stuff like this clip hints at.