Is this correct?
background="../../navagation-pic.png"
Would be much better putting
background="/path/to/navagation-pic.png"
or try if the above fails
background="http://url.to/navagation-pic.png"
Both should work.
I am wondering if the file is not being found, and therefore the page is timing out?
Not sure how bug the png file is, but you want to keep the image as small as possible - often a gif is better.