Almost any jamma/cga/standard res light gun game.
Area 51
Lethal Enforcers
Sharp Shooter
...
long list... should search for more. (Or look at my VAPs profile, I have most of them. Just check for CGA in the listings and not XY/positional based.)
Games you can't do:
Operation Wolf (mounted light gun, but different and not jamma)
Any "mounted" gun games (they are positional) like Operation Thunderbolt, Zombieraid, etc.
Sega Light gun games (House Of the Dead and Virtua Cop 1/2 are medium res and not jamma)
Infra Red games (mostly sega again) Jurassic Park Lost world, HOTD2,3,4 and others (typically medium res, not jamma)
Later "hunter" games like Big Buck Hunter Call of the Wild are VGA