actually, you can upgrade your bios through the os itself.. i'm not sure about the 9100 but i feel if the 5150 can why shouldn't it? although many people believe that bios upgrade through floppies is best, i did mine through the os and it turned out fine.. you just need to find the correct file to download for the bios upgrade..

There is a way to use the CD Drive with a Boot CDR and the Flash Floppy contents copied to another CDR, but it is a bit tricky to get setup for it. I have done flashes by this method twice and it is reliable. There is an extensive thread on the Latitude BIOS screens on this subject and has been made a "sticky" POST.

Updated the bios for my Inspiron 8500 by downloading the file from Dell website.  Just double clicked the file and that was all their was to it, machine rebooted showing updated bios.