Resizing or moving a custom header

I’ve inserted a custom header image on my website (http://www.thedumbingofamerica.net), but I’m new to this and unable to fix a major problem.
The image is sitting too low on the header, thus the jpg file is getting clipped. You can look at my other website: http://thedumbingofamerica.wordpress.com to see what it’s supposed to look like. How do I eliminate some of the blank space at the top of the page and move my title and image up?
I don’t like where the navigation bar is sitting but if I’m able to move the jpg and title of the website ‘up’, I think that problem would be resolved.
Thanks in advance for your help!