From what I've seen, Tumblr seems to be more of a site to post pictures and inspirational photos, etc. on. I had a Tumblr account, but never ended up using it.
I blog on Blogger. I like it because it's easy and free. I signed up before they updated the interface, and I still use the old one. Haven't really figured out the new interface, though. It's probably because I was used to the old one, but the new one is a bit confusing to me. I don't know if they give new members the option to use the old interface.
You can also find a lot of online help and graphics for Blogger. One of my favorite sites is
http://www.puglypixel.com/Katrina is an awesome web designer and puts free downloadable content on her site multiple times per month.
I've heard Wordpress is also good. I have an account with them, but never got used to their site. TypePad charges, so I never looked into getting an account on there, but they offer things that may be worth paying for.
If you have any questions, feel free to message me here. For reference, my blog is
www.thedoubtfulpixie.blogspot.com
