I don't suppose it matters hugely, just I have had most experience with GNU/Linux but could get my head around BSD if need be, I'm sure.
I was mostly referring to what would be regarded as the most free out of the box as such. I tend to avoid using non free software unless I have to. Of course when using a Mac or Windows machine, I usually have little choice but have never struggled to find anything for my own needs that works with Linux that is fully free.
If I'm honest, my knowledge of the licenses for Linux/GNU and or just Linux OSes is limited. I know enough to use it, and enough to know the forks and what is based on what. That's why I thought I'd put it to everyone here who could help guide me in the right direction as a base before I install something at home and get used to it, then get annoyed at myself for what I have supported whilst doing so.
For servers, I have always deployed Debian...as it's available...and there are ample guides.
Was just checking if I am as 'free' as I can be within reason.
Thanks everyone for the input so far, it has helped a lot!