Problems loading images into posts

For some reason the uploaded images in my posts change in their functioning. My first post images operate as I want: clicking on the image brings up an enlarged image. My later post images won’t do this; double-clicking brings up the comment window. I can’t get just an enlarged image. I have noticed the html associated the images if different. I don’t think I did anything different.
Any ideas what I am doing wrong? It can be seen at: ptolemeeplus.ca/antiquemaps/ The first two posts are correct. I attach the code if it means anything:
CORRECT:
<a href=“http://ptolemeeplus.ca/antiquemaps/wp-content/uploads/2012/04/MAP0047.jpg”><img class=“aligncenter size-medium wp-image-8” title=“MAP0047” src=“http://ptolemeeplus.ca/antiquemaps/wp-content/uploads/2012/04/MAP0047-300x237.jpg” alt=“” width=“300” height=“237” /></a>
INCORRECT:
<a href=“http://ptolemeeplus.ca/antiquemaps/?attachment_id=34” rel=“attachment wp-att-34”><img class=“aligncenter size-medium wp-image-34” title=“MAP0020” src=“http://ptolemeeplus.ca/antiquemaps/wp-content/uploads/2012/04/MAP0020-400x341.jpg” alt=“” width=“400” height=“341” /></a>