Hello Neil,
If I may suggest, Debian is most friendly distro for AMPRnet software.
There are quite a few amateur packages included by default.
Myself I use Raspberry Pi running Raspbian (mod of Debian Wheezy)
and desktop PC running Debian-7.4.0
I have also Ubuntu 12.04LTS but I put it aside in favour of Debian.
Best regards.
Tom - sp2lob