Addon, answering an aspect explicitly asked about in the question.
A "dd image" of a complete floppy disk, unless dd is used with special (skip/count) parameters, will always carry the parts that make a floppy disk bootable or not bootable along with it - dd if=/dev/fd0 of=temp ; change floppy to empty one; dd if=temp of=/dev/fd0 will create a bootable copy of a bootable original, unless special techniques (copy protection that works by (mis)using normally non-addressable parts of the media) were used in the original.