Problem with inserting images – I can only insert Thumbnails?

Hi,

I read the documentation (http://codex.ww.wp.xz.cn/Using_Image_and_File_Attachments)about inserting images and though I think I am doing it right (trying to insert the original file into my post) it insists on inserting it as a thumbnail no matter what I do. I can go behind it and edit the HTML but that is annoying.

Any suggestions as to what I am doing wrong? This seems like a user error but this user cannot figure it out and is feeling stupid!

Thanks!

H

P.S. I am just using the Default Theme and have not installed anything extra. I did change the header to a .JPG and reorganized the sidebar but that is it.