Corozal is a popular spot for expats and is the Northern most town in Belize which means you would be extremely close to the town of Chetumal, Mexico. Chetumal, Mexico offers medical services and more options for shopping which in include an American like mall and Sam's Warehouse shopping.
The Corozal district is 718 square files in area. Spanish is spoken more widely then English here, although you should easily be able to get by in English at least in Corozal Town.
Corozal town area offers low cost housing whether you are renting or buying, a sizable expat community and a pleasant location on the Bay of Chetumal, sometimes referred to as Corozal Bay. There are few sand flies and pesky bugs in most areas. Corozal has a pleasant sub-tropical climate with lower rainfall then southern Belize. It is generally considered to be safe and friendly. You have easy access by car, bus, water taxi and air to Ambergris Caye, other areas of Belize and the Yucatan.