Not a recent grad but having helped a number of friend equip kids for college here are some general thoughts:
1. Set a budget for a PC based on what you can afford. This will help define what machines to consider.
2. Look for discounts - educational, employer, affinity groups to see if you can save a few bucks. Also consider a manufacturer refurbished model if they are available. See if OSU offers software at a reduced price or free. Some schools, for example, offer Office365 for free.
3. Buy an all - risk personal article policy or ensure your renter's insurance covers it. A policy separate from your parent's policy will ensure their insurance doesn't go up if you file a claim. For deductible, look at what you can cover if it is stolen or broken (if you buy an all risk policy).
4. As for Apple vs. Windows it really depends on your preference. Chances are nothing you need to run will need better performance than running Windows in a VM on a Mac, but that adds a cost to the Mac since you need a VM plus Windows. You can get a higher spec'd Windows box for the cost of a Mac; although open box Macs at major retailers and Apple's refurbs can save you a few bucks.