I solved the problem. I found that I needed to format the USB drive with GPT format and copy the ISO file. I used Rufus for. Setting the BIOS to UEFI with the USB plug in booted the PC first time and allowed me to complete a new install.
Late year 2012 Dell laptops have BIOS with a UEFI option (A07).  Are there reasonble instructions on how to upgrade to Windows 8 and use UEFI rather than BIOS?  I would like to take advantage of secure boot and fast boot. In my case, I have no data to preserve at this time, so a clean install with formatting  (to GPT) is fine.  I have all the various Product keys for Win 7 and Win 8 upgrade.   Thanks, SMB
upgrade late 2012 Latitude 5430 to Win 8 64 bit with UEFI instructions 
available?