Currently I use imapsync (http://freshmeat.net/projects/imapsync/) to sync all of my email to shared archive folders on a vm with the cyrus imap server installed. I wrote a shell script that syncs all of my mail into an archive folder for the current year, then deletes the email off of the original imap server. From time to time I have searched for a way to write all of the archived mail to an indexed format that can go on a cd/dvd that needs no mail reader to search for, but have found nothing. I worry that 20 years down the road there will be no way to run the vm, the imap server, or a client to access it. So good luck ;)

For starters, use KDE (kubuntu). If the users are migrating from a windows world the transition will be much easier. Quite frankly gnome is garbage anyway.

In the KDE world there is kiosktool, see http://www.linux.com/feature/114306.