Which is better FDD or HDD?
In my experience, either USB-FDD or USB-HDD is what you want to choose. I believe it depends on how the flash drive is formatted. FAT32 and any derivatives or similar ones (ie, exFAT and FAT ) will probably be the USB-FDD option, while NTFS and EXT formatted flash drives will boot when the USB-HDD option is selected.
What is USB-HDD in boot menu?
If a USB drive isn’t available, the computer will boot from the hard drive. Usually, a “Removable Devices” or a “USB-HDD” would be the flash drive you’re looking for. Depending on your computer model and BIOS version, you can hit Enter on the 1st Drive option to open the menu and select the USB drive item instead.