To create a disk image from a floppy, you need to use Disk Copy 6.3 (I've got it and I can email it to you if you want it). However, Disk Copy 4.2 is fine for copying one floppy to another (although you can do that from the Finder) or for writing special format image files to floppies (although Disk Copy 6.3 will handle Disk Copy 4.2-format image files and normal ones, so there's really no reason not to use it).