i have converted quite a few. in fact, i make money doing it.
i usually install mint because it looks more friendly than ubuntu and i find it easier to work with. not to mention it plays mp3's out of the box.
i usually convert customers after their pc has become infected with viruses or they become frustrated that their pc is really slow and that nothing makes it better.
i copy all their documents onto a spare drive for temporary storage, boot the pc into the live disk and let them try it out for a bit. when they are happy with the operation, i install it for them, installing any useful packages and putting all their data back on. hand the pc back to the user and do a follow up; basically giving them a tour of their new pc and showing them how to do certain things. finally, make sure that you answer any questions they have and then let them go.
in a few days, talk to them again and ask them how it is going. if they have problems they will usually tell you. make sure they have a way to contact you and be ready for any phone calls that may come through in the following weeks. make sure that if they need you that you are there to lend assistance and walk them through the first few months of usership.
I have converted 4 users and influenced 2 of my teachers to use linux in this way. I have been using linux as my primary OS for a bit over a year now, but i have been using linux on and off for about 4 years on various architectures and varying ages/spec of machines from a power mac G3 @ 450mhz to my current athlon dual core laptop. I know I have a lot to learn still, but i use my pc in ways that force me to learn faster just because I need to learn in order to fix my system, on which i use quite a bit of 'alpha' and 'daily build' software, which sometimes cause it to break.







