How to change images in the blogs theme for header etc

I installed the blogsmu theme. I want to change the images on the home page. There is a little image that says Blogs and has rainbow color lines around it and I'd like to change this. There is an image of a monitor that I would also like to change. Do I have to go into the backend of the theme to make these changes? The site is roguevalleystylist.com and I want to change the home page images.