To upgrade a site from drupal 4.7 to 5.0:
I have several sites running drupal 4.7 that will want to be upgraded to 5.0 - here's how I'm thinking of approaching it. Mostly culled from a Lullabot video.
Prerequisites:
backups of site and db
all third party modules that a site is using are available
Process:
Log in as an admin user
Set the site to offline mode. Note that you can get a login while in offline mode at the relative url of /user
Disable third party modules/themes
Set the theme to a default - probably best to go with bluemarine
Create the new drupal dir (for my sites which are on a common code base - this means moving the symlink in sites and editing the apache config
If there are any changes to common code (.htaccess, spam checks for guestbook, other patches) that are in the common location - grab them now
Run update.php
Move third party modules and themes to sites/all/modules sites/all/themes
Enable third modules/themes
Run update.php
Test
Go to online mode