So much fun. I recently ported some old strategy games. Claude does it almost on its own http://replicated.live/blog/games
If the games had been for DOS, it would probably have made more sense to just run the original binaries in DOSBox-X or some other emulator. I think there is already some debug API that can be enabled. Or adding MCP or something similar to DOSBox(-X) would probably be a lot less work than to reimplement the games.
The entire point of the port was to add headless play for AI training. But porting the old interface and playing it in the browser was lots of fun. Can not upload that to GitHub, obviously.
IIRC Windows 9x & ME were based on (MS)DOS; but 2k and XP were based on NT, which was quite different.
(Note sure what those differences actually are, since I only started programming once I'd switched to Linux...)