A transitional title is used like a kind of "folder" that can help differentiate the different parts of your wedding. Many people use them for the different parts of their videos such as : Ceremony, Reception, & Honeymoon.
A Caption is small and located at the bottom of a frame in your video. All packages include up to 10 captions to be used throughout the video. Most people use them to describe certain moments or people. Like during speeches "Mother of the Bride," "Father of the Groom", "Grandma Lonnie," etc.