I have a Mac Mini from 2006 (Core Duo CPU) acting as my home server. It has 2GB, 64GB SSD and running Ubuntu 18.04 LTS. A 2TB external HD is plugged in to USB. My needs are modest so this set up is working well, running a Plex server, SSH server and OpenVPN server. I would like to rejigthings a bit, but the optical drive is slightly on the blink. I can get a net install of Ubuntu or Debian working, but a full distro will not work - I think the optical drive can only read the inner tracks of a DVD.
So, my question is, is there a way of booting a USB live Linux on this old hardware? I think the issue is that the machine is 32-bit and has a 32-bit UEFI and all the Linux distros have 64-bit UEFI support and falling back to BIOS will not work over USB.
Alternatively, can I boot from an external optical drive? Or what replacement internal DVD drive can I use?
Final question - will a 2TB SATA hard drive work in this old Mac Mni?