Are there moral, ceremonial, and civil distinctions within the Old Testament law?
The three categories of law you refer to are moral, ceremonial, and civil. No passage of Scripture explicitly distinguishes these three categories of law. Still, when we pursue a careful study to discern the purpose and intent of each law or grouping of laws, we soon discover that some laws are universal (apply to all people at all times), some are covenant-specific (pertain only to people living under the terms of the Old Covenant), and some are judicial (pertain to maintenance of justice in society).
The ceremonial category of law is virtually self-defining. The law of the sin-offering, for instance, existed only because a higher law was being transgressed. Obviously, the sin-offering was not instituted for the purpose of making atonement for persons guilty of failing to present sin-offerings.
Some believe that the civil law is simply an amplification of the moral law. While I would agree that there is an element of truth in this view, it is more accurate to say that civil law is the application of moral law in Israel's society. For instance, the law regarding the selling of one's daughter (Exodus 21:7–11) is not a universal moral standard; it very clearly belongs to the category of "civil law." The law reflects the social and economic conditions of that day, but its primary purpose was to protect the rights and well-being of the daughter—and that's where the "moral" category of law comes in. So we see that Israel's civil laws are founded on the higher moral law. The same can be said of laws regarding divorce and remarriage, slavery, indentured servitude, etc. These laws, which clearly belong to the category of "civil law," reflect both the societal norms of the day and the good and perfect will of God regarding respect for the rights, properties, and lives of others. The law permitting a man to sell his daughter was, ideally, a beneficial arrangement for both the man and his daughter. He received economic relief, and she benefited by becoming the wife of someone who could provide for her—a poor girl marrying into a wealthy family. However, in our culture, a man could not sell his daughter without violating her rights, so the moral principle underlying this law would be violated. For us, the application of the underlying moral law would be very different. So this law, unlike moral laws, is not a universal law. It does not apply in all times and all places. It belongs to the "civil law" category, and in it we see the application of a moral law.
Scripture itself all but spells out the distinction between the moral and ceremonial laws. Please read 1 Samuel 15:22; Hosea 6:6; Psalm 40:6; Proverbs 21:3; Isaiah 1:11–17; Jeremiah 6:19–20; Micah 6:6–8; Romans 2:25–27; and 1 Corinthians 7:19. These are but a few; the distinction is everywhere understood and taken for granted.
The two "roles of the law" mentioned in the sermon you referred to are clearly revealed in Scripture, though there is no text that explicitly defines these roles in just this way. It is clear that the law teaches us how to live (it's a light to our path, a lamp to our feet), and it is equally clear that the law identifies and condemns sin/sinners. I call these 1) the educative role of the law and 2) the judicial role of the law.