Yes, in Ohio you can carry your handgun loaded with one in the chamber. It wouldn't be of much use otherwise. You can also carry an extra magazine in a magazine pouch. It's legal, but once again, if you look like you're armed to the teeth, you're more likely to be stopped by the police. In addition, I've found from carryingthese past 5 years that there's only so much you can carry on your belt. My personal solution is to carry a full size Glock 22(16 rounds of .40). I carry two extra loaded magazines in my truck, but only wear an extra magazine if I have reason to be concerned about my surroundings or situation.
I'm sure that you know that you can't open carry in a vehicle (or even have a loaded gun in your vehicle) without having your concealed carry license. For that reason alone, I would strongly suggest that you take the training and get your license. In addition, many of the same laws (about where you can and can't carry) apply to both concealed carry and open carry in Ohio. Finally, there may be times that concealed carry would be more appropriate or desireable and being able to do both is a plus.