Confused at the genealogies in the Gospels? Wonder at who these Jews are, and what they are expecting, and why the Christ was born among them? What is this Temple place? Do you wonder where the titles “son of David” and “son of man” come from, and why they are important? Do you know where Christ got the two great commandments from?
I don’t recall ever reading the New Testament without some familiarity with the Old, so I have trouble imagining what that is like. I do know one is likely to miss a lot, though. The history of the people of the New Testament is established in the Old. The New quotes the Old frequently (often without saying so), and the meaning of many key phrases can only be understood in light of the Old. Christ and the Apostles were immersed in the Old Testament, teaching many people who were likewise immersed, and about things that are the culmination of the Law and many of the prophecies and hopes of the Old Testament writers. One reason for Latter-day Saints to read the Old Testament then is simply because it will allow them to better understand the New Testament.