Make sure you read these two pages<p><a href="http://drupal.org/node/548922" rel="nofollow">http://drupal.org/node/548922</a><p><a href="http://drupal.org/node/550130" rel="nofollow">http://drupal.org/node/550130</a><p>Before attempting to upgrade any drupal site to the newest release.<p>It seems simple in theory but in practice upgrading drupal to a new major release (they call it 'moving') is hard to impossible for any but the simplest sites.<p>For sites that are not so simple consider building a completely new installation using the drupal version that you intend to use and then migrate your data afterwards using a one-time-use script.