Here's a great infograhic on using Creative Commons for photos for blogging or pretty much most other non-commercial uses. Creative Commons licenses can be used for pictures, text, and more! Take a look at all the versions/license options HERE.
Hopefully it's OK to use a picture of one of their licenses... :-)
This one is for Attribution, Non-commercial, and Share-Alike uses... just like the one I have for this blog (see lower right margin).
