I think that the Westin River North has the best mix of location and amenities. The WRN is spitting distance to some fantastic restaurants, including Frontera Grill for Mexican food. Figure on $30 to park at any downtown hotel with in/out ability.

Gurnee Mills is huge, and then there are some older outlet malls just over the border in Wisconsin. These are the original outlet malls, and are not as busy. Many vendors are at both locations.