Maybe this is the problem with posting?

I found this in the blogger help forum...my settings are already set to the full page setting (I think the first option).  If you've noticed people aren't posting comments on your blog...check these settings!  If you can post on my blog, can you please let me know!?  Thanks!

"So, in one's blog SETTINGS, under the COMMENTS tab, where you have three
choices for how your comments will appear (Full Page, Pop-Up Window, or Embedded
Below Post),  it is the third choice - Embedded Below Post - which for some
reason disables the little pull-down menu where we are asked to "Choose A
Profile" and which prevents us from commenting.

Somewhere therein lies the programming error.

In the meantime, every time I come across a blog where I can't comment, I'm
going to ask them to change this setting to one of the other two."