We see James jump into the canal and his body submerged in the water. The following shot is of the family moving into the house in the field and James finally smiling. Now, a) you could intrepret this as he purposely drowned himself or b) the family was in fact able to afford the move to a much more nicer home. Given the rather ambigious ending I am hoping the latter, or would I be reading more into the film than thinking that the ending could be a dream/heaven/utopia.

The ending wasn't a dream as in a sleeping dream, it was his imagination as his life was slipping from him, as he slipped under the surface of the water. That is, yes, he killed himself, and his last thoughts were happy thoughts, of him and his family escaping the ghetto.