I took the battery out, unplugged everything, and waited for about 10 minutes before setting everything up again. Still got that screen.
Then, I disconnected the hard drive and both disk drives and got a disk boot failure message.
Next, I reconnected everything one by one. The message only came up once I plugged in the disk drive with the bootable disk in it.
Finally, I burnt the iso again onto a new disk. Still getting the "1. FD..." message.