Let me verify -- you are coming to Detroit specifically to go ride the hot air balloon?....
OK -- cool.
First, I've lived here for 20 years and have never heard of this - so don't expect it to be a big deal. I am sure you will have fun, but nobody here locally is going to know what you are talking about.
Second, Detroit and SE Michigan is completely a driving town -- there is no public transportation to speak of. As such, you will be renting a car. That means you do not need to stay anywhere near the airport, but can actually look at options where you can do things while you are here for a few days.
Pontiac is a good hour drive from the Airport. While the media made it look like it was part of Detroit when the Pontiac Silver Dome used to host the Detroit Lions, it isn't. It's a highly depressed run-down town 30 minutes north of Detroit. You won't want to be staying up there.
A couple options: Book a hotel in Ann Arbor and spend some time exploring one of the best towns in Michigan. It's about 20 minutes west of the airport, but about the same hour drive to and from Pontiac.
Another option: book a room at the Marriott Renaissance Center and stay in downtown Detroit -- downtown is going through a bit of a comeback, and you can take the roundtrip loop people mover to Greektown (restaurants), Comerica Park (baseball), Fox Theater, Casinos...
You can also look at the northern suburbs. Places like Troy are filled with hotels and things to do, from Somerset Collection mall to a myriad of restaurants.
If you specifically want an Airport Hotel for some reason - stay at the airport. It's about as convenient as you can get for the airport itself, but about as inconvenient for anything else. If you only play to fly in, drive to do your ballooning, drive back, stay overnight, and fly back, then that is where I would stay.
Otherwise, just check Hotels.com and select the airport area - all the hotels are within a one mile radius North of the Airport on Merriman and Middlebelt. There is nothing to do there except stay at the hotel and drive elsewhere to do anything else.
The biggest thing, I will repeat, is that Detroit and SE Michigan is a 100% drive-there town. Nothing is accessible without driving, except for the aforementioned Downtown Ann Arbor area and Downtown Detroit.
Drivers in Detroit are terrible, but not worse than Boston, Chicago, or Los Angeles...but those are the ONLY three places I would say have worse drivers than in Michigan, and I've lived in all of them over the years. The highways are in average shape, and they are bumper to bumper between 7 am an 9 am, and again between 3:30 pm and 6:30 pm. This is a highway town -- you drive from one place to another, and you drive every day. You drive to work, you drive to shop, you drive to restaurants, you drive everywhere. Lots of times you drive over bad potholes, and lots of times (from April to October) you drive in one-lane while the other three lanes in each direction are blocked off with construction. This leads to road rage and increased accidents during the summer. People in Detroit do not use road manners -- there is an air of "we created the car, therefore we drive as fast as we can and we cut off people who don't know where they are going"....Contrast that to, say, Orlando driving, where people drive defensively and look out for others. Also the speed limit in MI is 70 mph -- that means the average speed on all highways is 80 mph. Your not going to get killed driving here! But you are not going to find it easy to drive around if you don't already know the roads and traffic patterns.
