Without knowing the games, I can't say for certain, but I would strongly suspect most of the games that got commercially pressed at any scale in that timeframe have had their DRM circumvented effectively by now.
If I were the one doing this, I'd go look up NFO files for piracy scene rips of said games and see what image formats they provided, and then look into the software to produce those formats, since there were once a horde of different optical media ripping tools which boasted the ability to effectively produce more complicated image formats than ISOs which would permit exact replication of the media (or software emulation thereof).
A less effort-intensive way of doing this might be preserving an unsophisticated copy of the disc contents along with whatever modifications might be required to circumvent the DRM.
If I were the one doing this, I'd go look up NFO files for piracy scene rips of said games and see what image formats they provided, and then look into the software to produce those formats, since there were once a horde of different optical media ripping tools which boasted the ability to effectively produce more complicated image formats than ISOs which would permit exact replication of the media (or software emulation thereof).
A less effort-intensive way of doing this might be preserving an unsophisticated copy of the disc contents along with whatever modifications might be required to circumvent the DRM.