Working on www.kzoodems.com and the to-do list is long. Overall my goal is to upgrade the site from Drupal 5 to Drupal 6. The way things were done, however, makes this upgrade difficult.
In the early Drupal 5 days, there were a lot of all-in-one modules that added features. These modules extended the basic node in various ways, either to create a new, particular type of content or to complement your existing content types. The Bio and Event modules were two that I used and are examples of those that created their own content types. Image and Audio were modules that allowed you to augment your existing content types with new features. These kinds of modules were all the rage back then, but now they're passe and a lot of them were dropped in Drupal 6.
So, when you're upgrading from one major version to another in Drupal, your first consideration is "are all my modules available for the new version and is there an upgrade path," the changing models of module use between D5 and D6 present some difficulty. All the modules that are abandoned in D6 need to be migrated to modules that can be upgraded.
I've created an upgrade procedure diagram some people might find useful.
Drupal Upgrade Process