The last version of TempleOS is included, but I installed it myself, and I didn't bother to include most of the images that I just installed by myself in the credits.

I'm also planning to add earlier versions as well as the later forks at some point.

The vast majority were downloaded. A few I got when I exchanged compilation DVDs with someone in Finland in 2006 and 2009 (I uploaded the images on those to BetaArchive back then and they've made their way onto various other sites). The only ones that I have that were installed from images I dumped from original media that hadn't been previously shared were LynxOS 4.0 and MaxOS Linux (not to be confused with macOS, it was an obscure early-2000s commercial Slackware fork from a company that was semi-local to me; the CD was given to me back then by somebody at a long-defunct local computer store).

TOPS-20 4.1 and 7.1 are both included.

I'm not aware of any fully working TENEX images unfortunately. There are partial images, but last time I checked they weren't in a state that was even remotely usable.

tops20 is avalible to use at sdf.org :)

That wasn’t an operating system. https://en.wikipedia.org/wiki/Microsoft_Bob:

“Microsoft Bob was a Microsoft software product intended to provide a more user-friendly interface for the Windows 3.1, Windows 95 and Windows NT operating systems, supplanting the Windows Program Manager.“