All Pcs can r/w 720K or 1.44Mb disks. When using disks on the Amiga you must use DS/DD disks not DS/HD disks.
To read/write PC disks you need to have the PC0 and PC1 DosDrivers installed, CrossDosFileSystem and so on. For reading long filenames you will need the FAT95 driver from Aminet installed.
