if its xp you will need to create an msdos start up disc.place a floppy in the drive click on format and then choose create an msdos start up disc.
next transfer the bin or rom file to the floppy.
next make sure the computer is set to boot from the floppy drive first in the bios.
then the computer is restarted with the floppy in the drive and you follow the instructions given to you by the manufacturer on what to type.
be careful and read all the instructions first as if its the wrong flash or you get a power cut or the computer crashes you will be left with an unusable computer.
its usually very easy to do just be careful.