I'm not sure exactly what you're looking for.
If you put a floppy in the drive, right click it, and select "format",
you'll be given a checkbox to create a system diskette.
That will permit you to boot into what is basically DOS. (I have read claims
that it differs from a real MS DOS boot, but I'm unaware of the distinction.
I believe that when you boot from the floppy, you may be informed that
you're starting Windows ME.)
The main problem with it is that there won't be much free space on the
diskette for things like updated mainboard BIOS files.
Even Vista X64 preserves the ability to generate a boot floppy. I find that
I don't need boot floppies very often; I use a bootable USB thumb drive.
HTH.
Return address scrambled. Replace nkbob with bobkn.