For what you are describing, the IIUI Exporter is the utility specifically designed for this task. It will do the mass export of the system, preserving the library structure and providing as much meta-data as you desire.
The IIUI Exporter has been used on millions of documents and is available in one-time use liceneses for short-term projects, standard site licenses, bundles, or enterprise licenses. For more information, please contact me below or visit our web site at http://www.iiui.com
Innovative Ideas Unlimited, Inc.
"The IIUI Toolkit for Domino Document Manager: Increasing your productivity and returns with Lotus software."