The final reason I'm offering to try to entice you into reading the Old Testament of the Christian Bible follows. That does not mean that it's the only other reason; it's just that I won't argue the point any further, unless you want to contact me directly or via the Comments section below. I want to know there's a fight to be had before I waste too much time lacing up my gloves.
As the Apostle Paul writes to his young protege in the book of 2 Timothy, "All Scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness." When Paul refers to "all Scripture" here, he may not be exclusively refering to the Old Testament--some of the New Testament writings may have been recognized as Holy Scripture by this point in history. But certainly the vast majority of what the apostle is pointing to here has to be the Old Testament. And Paul says that it was inspired by God, breathed by Him, and that it is good for us. Do we need to argue any further? If it's inspired by the Holy Spirit of God, and it's good for us in all the ways it describes, why would we not read it? Unless we are so pathetically lazy or distracated by the world that we won't even lift a finger to help ourselves.
But, you may say, in this your final argument, it's just so hard to understand. And parts of it are supremely boring to read through. Fair points both. I don't recommend that you start off reading the ceremonial regulations concerning mould on the walls of your house, for instance (that's in Leviticus 14--a good place for the beginning reader to avoid). But there are stories in the Book of Genesis that are fabulous, and make for a pretty rewarding read. Also the stories of David's life in 1 Kings and 1 Chronicles are both familiar and quite interesting. And reading the Prophets can be absolutely terrifying--there are sections that seem as if they've been ripped right out of today's headlines.
As far as it being hard to understand, I'll offer you this rebuttal: What isn't hard to understand, when you're first starting out? We don't intuitively understand baseball statistics, or algebraic equations, or internal combustion engines, or software coding, or hardly anything else that we have to approach for the first time as novices. But if we care about the subject matter, we'll stick with it until it starts to make sense, and we''ll keep with it as we begin to understand more and more of it. And if we keep to it for years, and even decades, our understanding at the end will far surpass the little complaint that we had at the beginning of it being just too hard. There are things that I learned just this past year that helped me understand some of the writings of the prophets that I had misunderstood for decades before. But that doesn't mean there was never any reason for me to read it until this past year--if I hadn't had that background of building line upon line and precept upon precept, I never would have gotten this far. And there's still more room to grow!
Don't let the idea that you're just a novice daunt you. If you never start, you're never going to grow. And the rewards are tangible. What does Paul say is the payoff for spending time with the Scriptures, according to 2 Timothy 3:17? "That the man of God may be complete, thoroughly equipped for every good work." Isn't that what we want to be? Complete, and ready to be useful to our Lord and Maker.