What software is best? I want to set up a blog with the following qualities. 

1. The blog must be hosted through my existing domain and under my full control.
2. The blog must be editable either online (my
hosting supports Perl, PHP and MySQL) or through Mac OS 9--9 not X!
3. The blog must be highly configurable, particularly as concerns templates.
4. The software must be free or cheap, and not put my content under
any copyright restrictions or impairments.
5. The software must be easy to install and stable; I can write PHP
and Perl at need, but I am not a Unix hacker.

I would prefer if the blog could use HTML entries at least by request,
rather than requiring some special mark-up language.

I'm pricing this low because I'm sure someone has the answer right on
their fingertips. I would be happy getting a short list of options,
but, for now, I know too little to start looking intelligently.

Thanks!

Check out ExpressionEngine by pMachine. I have used this on several
sites and it's by far the best CMS (content management system)/blog
software available. It's not free but for the price there is nothing
that even comes close

http://www.pmachine.com/

"ExpressionEngine is a flexible, modular, feature-packed web
publishing system that permits virtually any kind of web content to be
managed - from a no-compromise weblog, to an advanced interactive
magazine, to a corporate site requiring the power of a full-featured
content management solution."

We've been using Serendipity Blog software for a while now and it's
extremely easy to install and use, very powerful and very flexible. It
does everything you requested. It runs on a PHP/MySQL platform and,
unlike pMachine, is completely free (open source).

Check them out at: http://www.s9y.org/

Stacy