If you have downloaded the file for your region to your PC you should have an .EXE file just double click it to allow it to extract and create a folder with the following file PANA_DVD.FRM then just write this file (Not folder & file) to a CD-R and insert into your player and update should run. Do
NOT power off player as this could brick the player requiring return to dealer, update could take 5-6 mins to perform update
link to update proc PDF
Note also quote from Panny site
The firmware update disc requires to be created with ISO9660 format. In case you are creating the disc on a Windows Vista PC, Windows Vista standard writing application does NOT support ISO9660 format. Please create with a supporting writing software