"I have a bios password on the computer, so
every time computer restarts I have to enter the
password. Could it be because of that?"
It certainly can. Windows needs to reboot itself at least once during the install. Remove the bios password for the time being. You can put it back on later if you wish.
I would think the supplemental disk is just that - supplemental, and not necessary. When you retry the install, it would be good to wipe the drive and delete the partitions and start afresh. But your data needs to be backed up first if you do it that way.