I don't see any boxes, but since you've got 53 validation errors you might consider starting with making good xhtml and see if that improves the issue. Are you using IE?

http://validator.w3.org/check?verbose=1&uri=http%3A%2F%2Fblog.covenantradio.com%2F

Sorry -- I should have posted that I got the boxes out of there! it was a setting in the back office.