Nec Firmware Update How Do You Update Your CD/DVD Drives Firmware?

How do you update your CD/DVD drives firmware? - nec firmware update

OK, here's my drive (I think):
NEC DVD_RW ND-2500A
Driver Date - 01/07/2001
Version - 5.1.2535.0

I need to update, because I can not burn data to DVD-R discs is over, I've tried all kinds of brands and can not read, even among themselves, except that the CD they are blank.

Where do I go to download an installer for the updated firmware or something else? Can someone tell me exactly? I'm tired of searching, but I'm not sure whether I read that also must be careful? How can it be useless if you screw up?

Thank you.