It is advisable to keep back-up disks of your programs and files on floppy disks. Never move your hard disk unless you have readied the disk.
Hard disks are sensitive to smoke and dust.
Keep both away. It is likely that all DOS files have been transferred to your hard disk also. Making a disk ready is a complex procedure and should not be attempted unless you know what you are doing. If you have a hard disk of more than 30 megabits, DOS will see only 30 megs. If you want to use all of the disk a new partition must be created.