Check out the Resolution patterns on Avia. Clear vertical stripes in the 6.75Mhz patch in the lower right corner would indicate you are getting the full resolution out of the DVD format.
Sharpness is usually abused (set to high) causing white highlights on vertical black lines as seen on the Avia sharpness pattern.
A good way to set it is to view the Avia sharpness pattern and lower sharpness until those white highlights go away. Now look at the resolution pattern across the top and see if the right edge has blurred into a gray mush. If so, you need to settle on a compromise between reducing the edge enhancement or reducing your resolution.
If you tell us what model TV you have you might be able to get some specific advice.
Other things that affect the apparent "sharpness" of the picture are focus, SVM (should be off), and convergence.
former ISF Calibrator
If you can see my pixels, you are sitting too close.
Sony XBR75X940D, Sony XBR55X930D, Samsung UBD-K8500, Oppo BDP-103, Oppo BDP-93,