I can tell you from personal experience, both schools are excellent. If you are thinking about not going to U of Minn because of the price of a ticket, that's one thing, and thats more up to you.
If you are talking about the cost of tuition and living, then that's another I can talk about. If you are out of state, and are going to OSU, then you will pay $20,000 out of state fee, but this is only for 1 year, as it is almost automatic that you get state residency after a year. You can avoid this fee if you are married and your spouse starts a full time job in Ohio. Otherwise, tuition is approximately the same as other state schools. The cost of living is low, population is somewhat less diverse than twin cities, but there are decent things to keep you interested in Columbus. One thing is Columbus and Ohio state are widely spread out (with little public transportation you will be driving a lot). Some live within walking distance of the school, but many chose to live further away and drive.
U of Minn. Excellent school with good reputation also. The out of state tuition when I was accepted was waived for the first year, and you get in state residency for the remainder of the years. I heard that this was standard for all out of staters. I would say that weather is a little colder than Ohio, but nothing horribly worse. It definately snows more, but there are also a lot more outdoor activities there (remember, state of 10,000 lakes). Also, the twin cities are very alive with much more ethnic restaurants and activities.
The decision that I made came down to this: Columbus was more or less NEAR the city's downtown...Minnesota is IN the city. There are many pluses and minuses to both. Good luck.
sscooterguy