Sorry, I also forgot to mention http://wordpress.com. I must say they make great software (from a backend perspecitve). Whereas Blogger is beginner friendly and has a really simple "wizard"-style interface, WP might need a bit of getting used to, but it is much more powerful.

I have used WP's software (@ wordpress.org, not the hosting service which is the .com) and it is very nice. Also ad-free except for a little unconspicuous credit at the bottom.