This site lets you use a Bookworm database to compare the language spoken by every president in his State of the Union addresses.
Choose from the left and the right the two presidents you want to compare. The two columns will populate with the most statistically distinct words between the two speakers. Click on any word to see a chart of every president and how much they've used it.
Keep in mind that the State of the Union has changed a lot in its history. Of particular importance to understanding these charts is knowing that it was written, not spoken, before Woodrow Wilson.