Can you see? It might actually be different on your screen, but on mine, finally! The header is the same width as the two columns... (hallelujah chorus!) I did this by editing the html and changing the width. I don't want to do it again, its a bit like going to the dentist!
This is where I found some helpful info: blogbulk . Hopefully it might help someone else too!
Now, how do I get the photos bigger? hmm, back to research.]
Let me know what you think!