I've been getting interested in retro computing lately, and I was wondering if one thing was possible.
If I were to run GOG's installer for an old DOS-era game, take the game-specific data files including original EXEs, and burn them onto a CD, would I be able to put the disc into a computer booted into MS-DOS, and run the game using that? Would it be as simple as that, or would there be other factors to consider? Any help is appreciated, thanks.

I think for most, if not all, DOS games your idea should be fine. After all, for DOS games the GOG installer is essentially putting the original game files into a folder (maybe with a tweak or two?) and using DOSBox to emulate a DOS environment and launch the games from within.