boot from external dvd drive

Good afternoon, my situation is as follows. I have an optiplex 210 L and I try to boot a hire's bootCD from an external DVD drive, however the bios does not recognize it. Just me are these options
* Onboard or USB Floppy drive
* Onboard SATA Hard Drive
* Onboard or USB CD-ROM Drive

Was looking the support official and there is a update for the bios but not am sure of that that resolves the problem. Any alternatives? It mkas strange is that if I try to boot from a pendrive silo recognizes and me it displays as:
*Usb Storage