Dear Julie,
I’ve written some tailored code for your logo size: in order to stretch the menu and logo, please go to “Appearance -> Editor” and add the following lines to the very bottom of “style.css” (should be opened by default):
#nav-primary li a { width: 222px !important; }
#logo-wrap #logo a { width: 240px !important; }
#logo a, #logo { height: 210px !important; }
#nav-primary ul li ul { left: 246px !important; }
#nav-primary li li:first-child a { width: 225px !important; }
and click “Update File”.
Another option would be to resize the logo image prior to uploading it, so that its dimensions fit into a 116×120 px rectangle – this way you won’t need to add the above code to make it fit.
Sincerely,
Andrew | Satori