The best format is the one that works best for you. To some extent it will be personal preference. Lots of people for instance like Wordpress, and I agree it is a capable platform - I just don't like using it.
I think Blogger is a little bit simpler to use than Wordpress. I haven't ever tried Typepad. I kind of like Weebly as well. You can do quite a bit with Weebly and they seem to always be trying to improve their service. It is a bit more of a learning curve, though, in my opinion.
If you want to pay a little for it, Squarespace is an excellent blog platform.