Windows 3.1 Download

I am messing around with different operating systems on virtual machines. I am wanting to try the very old Windows 3.1 OS. I have poked around Google search results, Stack Exchange, and the official Microsoft website, and I have been unsuccessful.

I originally thought that the "Windows 3.1 Installer v2 " (http://ift.tt/1CnEl7C) was the Windows 3.1 OS, but that is, of course, not it.

I do not want to download the Windows 3.1 OS from an unofficial or malicious website, or a torrent. It must be legitimate (and free)!

I would also be interested in what free and legitimate operating systems you would recommend. I have already played with Ubuntu and Ubuntu Gnome).