Blend together cheeses until smooth.
Stir in Worcestershire sauce, celery salt, and onion salt, adding more to taste if desired.
Shape into a ball and set on serving plate; cover and chill for 2 to 3 hours, until firm.
If desired, score vertical lines with a knife to resemble a pumpkin.
Toss walnuts with paprika; press into surface of the cheese ball.
Break pretzel rod in half and insert in the top for a stem. Use a real stem, if desired, just rinse and insert in the top of the cheese ball.
Arrange crackers around the cheese ball.