Tolsti, try and find a book called "Flying Tonight-a beginners guide to aviation" published by Ian Allan a few years back. Im not sure if its in print, i havnt seen it for a few years, but you can probably pick it up in various places
basically it covers most things that the passenger will cover in the course of his/her flight, explains them in a lighthearted and humourous way, with relevant diagrams or pictures. I suggest purchasing/borrowing a copy, loaning it to your friend.
Alternatively, i recall on "Airline" or some such programme, they followed a group of pax who were on a specially chartered plane as part of a course for people who had a fear of flying, basically, they had a briefing by pilots of what to expect, they went up for a quick jaunt in a 737 or such then came back. most overcame their fears to some extent.
best of luck anyhow
TP