As everyone else said, they’re floppy disks with the plastic case removed.

Since you found them in a church, could they have belonged to a church bell system? I’ve seen other church bell systems in the past where the songs came on weird mediums.

This is just a random guess, I don’t know why anyone would remove the casing.

The X in DirectX is a placeholder, because it’s a suite of APIs.

DirectShow, DirectSound, DirectMusic, Direct3D, ect.

Its like “Direct____”