Don't miss Pioneer Village. It is a great hidden treasure and one of those places that may not be around ten years from now. If you are traveling through Michigan, one of the best car museums bar none in the USA is the Gilmore Museum in Hickory Corners, just north of Kalamazoo about 30 minutes from I-94. This is an amazing car lovers paradise and will be the new home of the MAFFI museum. They have about 250-300 cars on display of all types-many world class automobiles that you will not see anywhere else and the restored barns and grounds are picture perfect. It is by far my most favorite car museum in the US.
In terms of staying in Dearborn, treat yourself and stay at the Dearborn Inn (A Marriott hotel). It was built by Henry, you can walk to the Museum/Village and it is loaded with Ford memorabilia. If you don't stay there, The Henry is a great and recently renovated hotel (also a Marriott property). Have a great time in Michigan!