Good thoughts fellows. I'd like to contribute something. I'm already sorry
for a lenghty answer, but I hope it give some insight.
a Previous thread here shows that many of us have switched to free software
step-by-step, many small steps after another, so I'd suggest using that
strategy. Show them small things that are relevant /to them/. Be cautious,
because those things and tasks are likely to be completely different than
what's nice and neat for you.. so take a note on what tasks and how they
perform, look for alternatives and play around with those programs yourself,
so you can support their experience.
Please keep in mind that many users don't mind about the four freedoms. I
found out that the best way for those who value practicality, is to show them
the aspects of free software in practice. The ethical issue is harder.
There's no pushing it. Just let the question "why would anyone make this
software and give it out for no money?" arise, and then address that with
your reasoning the way they might understand.
One day my father asked about copying Vinyls and C-tapes to a computer, if
that's possible. I teach my father to use audacity. Not all the bells and
whistles of it, but a very basic set of tools and concepts he already
understands from the analog world. He already knows the equalizer, amplifier,
selection removal, zooming and exporting to file. He knows the practical, or
sound difference between lossy and lossless audio files.
Sure you could do all these things with proprietary software, but these
programs tend to bug, nag and wear off. You often are required to tell the
dev you're using it, paying for it, and throwing it away when it wears off.
What's neat in this software for him is the fact he's completely libre and
allowed to use old version of this "sound thing" on his old laptop. It
doesn't nag, brag or bug him about anything irrelevant. It just does what he
tells it to do.