No, you can't bring it back to a floppy... The only way you can record anything to a floppy is to use a midi program... like cakewalk... You could then record your tune to the computer then make a disk... although that is going to take a lot of research on your part... I suggest you check this site on midi recording...
http://www.tweakheadz.com/how_to_get_started_with_midi.html Another way is to use your built in sequencer in the keyboard itself... I know the PSR 540 and 550 both have 16 track built in sequencers you can save the files on a floppy. That's how I record all my stuff on the psr2000... I play each part on diffrent tracks on the keyboard and save it to disk... I then do all the mixing on the board... panning left and right and changing instruments and bringing volume levels up and down on each track... Then I hit the play button when I'm ready and it records to Audition 1.5 (Which is a Cool edit upgrade, Adobe bought cool edit..)After, I can do vocal tracks into a mixer into the computer... All done in audition.. I'll try to explain further...
Pro edit is an audio program it only records audio, or wave files from your keyboard.. They are recorded exactly as they sound. You can do track by track up to 128 then use effects and mix them down to a single wave file that you'd put on a CD, or make an mp3 out of... Cool edit is pure recording software... There.
As for the Casio... The model you want they sell mostly in europe and have not seen one around these parts... As a beginner it's important that you get a board a lot of folks know about... That way when you need help you more likley to get it...
That's all for me.
DJ