dolphin_oracle
the difference in the boot menus is because on the live-USB the bios/mbr boot uses syslinux and the UEFI boot uses grub2. An installed system will always use grub2. the “customize” option replaces the function keys on the mbr/bios boot. They functionally do the same thing.
As to why you have a 5 minute delay on the fujitisu, that is a good question. perhaps running with the bootchart option enabled will shed some light. I think there is a live boot log under /var/log as well that might be beneficial in this case.
As long as your PC’s bios can boot a gpt partition table, you should be OK with that combination, although its not 100% and its hardware dependent. The mbr still needs written to the disk on a bios boot, but gpt is supposed to have a “protected mbr” area, that while not a real mbr, will serve the function. I’ve got a least one PC that will not boot bios/mbr on a gpt disk, although that PC is very very old.
