Another Boring Topic has started a series on the development of Windows and they're quite detailed while being some of the clearest on the matter I've seen and it appears he puts a lot of work into these. If you're interested in this subject matter I highly recommend his videos
Part 1 covers Windows 1x which I would bet many you have never seen and there's a reason for that.
The Rise of Microsoft Windows Part 1: Windows 1.0 (runtime 1:02:12)
https://www.youtube.com/watch?v=vqt94b8bNVc&t=10sPart 2 just dropped and, you guessed it, covers Windows 2x
The Rise of Microsoft Windows Part 2: Windows 2x (runtime 02:03:03)
https://www.youtube.com/watch?v=oNFqsvK20mQ
