EZPX is a lightweight photoblog engine with all the features you need and a user interface you'll love to use. It can be used as a standalone photoblog application or as a Flickr agent. It features an easy installer/upgrader that notifies you when an upgrade is available, support for templates, and much more.
tmphoto is a Web photo gallery with a fairly advanced metadata structure, allowing photos to be described in terms of place, category, persons in the photo, and events. The places, categories, persons, and events can be further described. It offers a nice browsing interface based on the metadata.