PAndersen,
Yes that's true. You can go into the BIOS and disable the floppy drive at bootup. Also, you can set a BIOS password to keep people from changing the settings.
HOWEVER, if we're talking about real[/red] security like at a workplace where anyone can walk up to the pc, then that wouldn't hold up well. No matter what kind of app you install, you can always FORCE a shutdown by holding the power button down until the pc shuts off or simply unplugging the pc. And as I mentioned before, you could reset the BIOS to get rid of the password protecting the floppy drive. Using a boot diskette, you could then gain access to DOS or possibly even safe mode, exposing the disk's contents.
Conclusion: upgrade the file system to NTFS if you want to be sure