I would. Unless your wedding is really casually you should use appropriate titles when addressing the outer, mailing, envelopes. The male guest’s name should be spelled out, but not the female’s.
For example: Mr. and Mrs. John Smith
If he’s a doctor, judge, in the military, the format would be the same with his title being Dr. or The Honorable or Captain, etc… Ex: Captain John Smith, U.S. Navy and Mrs. John Smith.
If the female guest is the one with a career title her name would go first with his underneath: Dr. Jane Smith and Mr. John Smith. But the “and Mr. John Smith” would be written beneath hers.
It’s technically not proper to put The Smith Family on the envelope if you’re inviting the whole family, but no one is going to call the etiquette police on you. When inviting a family put the parents’ names on the outer envelope and each person’s name on the inner. Another option is to send one invite to the parents and the second to adult (over 16) children in the household.