EXAMPLE: How Prince Escalus might act around Lord Montague: Roll his eyes and sigh, as if he blames Montague for Romeo's killing of Tybalt and disregard for his own direct order for peace, yet still feels sorry for Montague's loss of his son. He won't do anything more than this because he is a weak ruler who knows that the Montagues and Capulets have even better connections to the citizens of Verona than does he.
These characters are "odd couples" and normally have nothing to do with each-other.
Assuming this is after the deaths of both Romeo and Juliet, Paris and the Nurse wouldn't have that much to say to each other. Paris truly liked Juliet and wanted her for his own. He had no hidden agenda, and he was saddened by her death enough to visit her tomb just before Romeo got there that fateful night. He is a good person who is willing to fight for what he believes.
The Nurse was so outgoing for a servant in the house of the Capulets. By this point in time, she should feel so much guilt for not being a better "nanny" or overseer to Juliet than she was. She got caught up in the romance at first, and then backed out on Juliet when she needed her most. That was why Juliet kept her fake death from the Nurse. Because of this, the Nurse would have lost her outgoing nature. She would be subdued and quiet, only speaking when spoken to.
If these two were to sit down together, Paris would be the first to begin the conversation because of his manners. The Nurse would answer him, but would rarely look him in the eye. She would feel guilty and uneasy around such a good man who could have been as good of a match for Juliet, and she still would've been alive had she chosen him. She would hold the conversation, but would answer short replies with her eyes cast down. He would sense her discomfort and abort the conversation in a polite way.