I live close by in Neudorf and I used to live there, it is a really nice area specially during summer, it has a lot of outdoor activities specially for biking, swimming and running and you can practice almost every sport out there. The only thing is that Wedau is fairly small and you wouldn't have good possibilities for shopping and moving around, it is a bit disconnected from everything and you can only move around with car.
I would suggest you to look in Neudorf (south or north) or Kaiserberg, they are nice areas in the city and very central. It would be easier to to get to the main train station and taking a train for your husband or even taking the proper highway (Autobahn) if he planning to drive. If you move to Neudorf south or north you get the best of all, you are around 20 min walk way from the main city center, around 15 min walk from train station, 2 min way with the trams and with the bus and you still are 15 min bike from the regattabahn in Wedau.
It depends what you and your family are looking for but Dortmund is bit far away from Duisburg around 45 min one way with the train + the time your husband needs to get the train stations, I wouldn't count less than 2 hour each day both ways and with the car is not better. Perhaps you should consider a city closer to Dortmund, Bochum or Essen but if you still go for Duisburg, I can only recommed the city.
I hope this help you, If you need more info just send me an e-mail.
Hi lived in Duisburg as well, and even that I don't come from a english speaking country, they would try the whole time to speak only english with me. So it is normal.
You shouldn't take it badly, believe me those are just trying to get be friendly anyway I guess you are at the uni and I hope by now you got to know some folks out there but I will give a tip.
As stupid as it might sound, well just answer them back in German, after a while they will realized that you just want to talk in german and not english, just watch out for the USA-fans they are bunch of them out there, once you are discovered they will try by every mean to chat only english.
Anyway if you want to go for a beer at finkenkrug or fährmann, send me an e-mail. I promised I speak to you in german, perhaps I can introduce you to some german friends.