Hi friend:
I think just age on a disk will not damage your system. It will be fine. The only way the disk will not work is if there is something wrong with the disk, like maybe the metal part was screwed or the disk inside was fu*cked, as if a needle was poked thru it. I have disks 15 years old and they work just fine on my amiga 1200. But of course I kept them in good condition. Just be careful, only use disks that seem to be in good condition. As I said, age is not the issue, is how well kept the disk is. Also, you can buy an 'extra' floppy disk drive, it hooks right into the amiga and then you can use it good and protects from using the include floppy drive. An external floppy disk drive is super. Also, if you play games that come in two disks, if you have the external drive, you can use both together without having to swap disks.
Cheers!!!
rednova