It is very intimidating to take on the task of blogging through such a book as Romans! Many regard it is as Paul's masterpiece of theological reasoning. There is a power contained within it that has changed lives, birthed churches, and launched spiritual movements and reformations. Yet it is precisely because Romans is such a critically important work that we must give it all the time and attention that we can.
Paul begins this letter - his longest in the Bible - with the customary format of a) self-identification with an attendant description of himself and his calling, b) the addressee, in this case the church in Rome, and c) a statement of blessing and thanksgiving. Most of Paul's letters were written to churches and individuals that he knew well. Romans, however, is more of a reach for Paul because he had not yet visited the city.
I believe the body of the letter starts with Paul's bold defense of his faith in verse 16: "I am not ashamed of the gospel, because it is the power of God for the salvation of everyone who believes: first for the Jew, then for the Gentiles." He then sets out to explain and expound upon the Gospel. This Gospel is predicated upon faith.
In order to convey an appreciation of the depth of God's grace, Paul begins the story of salvation by focusing on God's wrath. Nobody likes to hear their sins cataloged and parsed as Paul does in the final half of Romans 1, but he isn't really interested in coddling his readers! Paul understood that unless you can grasp how sick you are, you will not be interested in the cure offered by Jesus Christ.