Katherine the original image I've worked on is the full size, with the crop what I think you're looking for. I'll remove the bit of tree from the top.... The rest I just figured you'd enjoy looking at...
Have at 'em! Wave the cursor over the image and LEFT click on the "Save Photo" icon... An alternate method to save any of the various web-ready sizes is to click on the enlarged image, select any size of the sizes you see above the image (S,M,L,XL..,O), then RIGHT click on the enlargement to bring up the menu. "Set as Background," for desktop background, "Save Picture As..." for saving the size. Experiment with different sizes until it fills your screen.