sounds as if each time you work on a document Word2010 is saving it as the 'global template' Normal.dotm http://support.microsoft.com/kb/918064
When you open a new blank document it should be a .docx But if you have changed the global template with your text on the page then the .docx will have that text there instead of being blank.
When you first open Word which is your (supposed to be blank) blank document opening as? .dotm or dotx?
That is important so can ascertain if global template is being changed once or everytime.