phpBB • Free and Open Source Forum Software

I want to remove the asterisk/box that's present where my site name is. I tried deleting the name but it just left it with the asterisk and box still there. I'd also like to move the navigation bar to be right above "mark all forums read" instead of on the header itself. Screenshot of header here for reference. Also is there a way to change or remove that grey-and-white diagonally striped part that's wrapped around the header and forums?