So I bought a used copy of Warhead. Tried it once on my 512k machine, worked fine, played for a few hours, but there was no music. Vaguely remembering that there was a 1mb requirement for music in this game I booted it in my 1mb machine. Two bombs, then three. Put it back in my 512k machine, no bombs but instead psychedelic flashy colors and message "boot error". Repeat, same result. Repeat once more, now the thing goes to desktop as if there was no disk in drive.
I examined the disk and found something strange - inside the metal hub, the black nub that's normally fixed in the middle was rattling loose, as well as a spherical, metal-colored flat object the size of the black nub. I've never seen anything like this. I don't even know what that part of the disk does.
From what I can guess, the black nub is some kind of shielding that protects the plastic shell of the disk from wear as it spins, while the other hole in the hub is used to actually spin the disk. Problem is that I have found no documentation that would identify parts _inside_ the hub, let alone explain what's necessary for them to operate right (basically, whether or not the plastic nub missing would potentially damage the magnetic disk by allowing the read/write head to get too close to the disk's surface). All I've found says that the metal hub's job is to precisely control the disk's orientation, without an explanation how.http://tinypic.com/r/2j4pzwz/5http://tinypic.com/r/14niljs/5
What should I do? Is this disk salvageable? It looks like I could attempt to drag the things out of the hole with tweezers, but I haven't tried it out of fear of making things worse.
EDIT: Added a clarified picture.