Any help appreciated, thanks,
Neil Parry
NP,
Absolutely. The doc section you refer to, http://docs.moodle.org/en/Moodle_migration#Migrating_a_complete_Moodle_site, describes the process of migrating a Moodle installation to a new server. This can be done either before or after upgrading from 1.5.3+ to 1.6 and/or 1.7, which must be done before upgrading to 1.8 because that's where you need to migrate the database to Unicode (if you are in a hurry to free yourself from the old server, migrate first). 1.6 is the first version that supports Unicode as an option, and the capability to migrate your database to it. 1.8 requires Unicode, so you need to do the database migration while you are at 1.6 or 1.7. See http://moodle.org/mod/forum/discuss.php?d=76704, http://docs.moodle.org/en/unicode, http://docs.moodle.org/en/Upgrade, http://docs.moodle.org/en/Upgrading_to_Moodle_1.6, http://docs.moodle.org/en/Upgrading_to_Moodle_1.8 (which also discusses roles and capabilities and other issues), and http://docs.moodle.org/en/Database_migration (whew! ).
RLE
Neil