The digital revolution should have made preserving the past easier, but instead, it feels to me like we’ve only lost access. The games and programs we grew up with didn’t grow up with our computers, and now most live only in our memories. Well, unless you know where to find them.

While there may be a host of sources on the web for finding old software, there’s perhaps no collection as complete as The Internet Archive: The non-profit has a collection of CD-ROM files that span decades. As of this article, the archive has just under 46,000 entries, from games to software you might have used growing up in school. Chances are, if you remember it, it’s in here:

This is a wide and variant collection of CD-ROM based software, that is, software that came on a CD-ROM for installation on computers, or played in consoles. Ranging from applications and games to gatherings of public-domain software or clip art, the heyday of the CD-ROM is roughly 1989 to 2001. In all cases, the capacity of the CD-ROM stayed steady at 640-700mb a side, although some used tricks to claim they had more (due to compression, or adding up both sides of two-sided CD-ROMs).

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Archive

Additionally:
Internet Archive Arcade - Link 1

Revisiting old games is so hit and miss for me. I went back and played a bunch of NES & SNES games not long ago and the only ones I still loved were the Super Mario and Zelda games.

I found a CD online for unlimited old-skule games (mostly Atari) for, like, $2, shipped ...
It's backed by "Steam", updates regularly, and it was a great investment ...

For most others I just use MAME ....