Düsseldorf (BRD) - what to see, where to go?

I'm going to Düsseldorf (Germany) next Wednesday to collect my daughter from the Airport in the evening.
So we were thinking to take a day off and visit Düsseldorf.

Any tips what to see and where to go (photography wise)?
* is there a fine photo store with analogue stuff?
* a photo museum of gallery worth visiting?
* local sites to photograph?
* and a good restaurant for dinner?

I think we'll be going to the Altstad during the day, maybe visiting the Lambertuskirche and the Museum Kunstpalast.
Thanks,
Bert from Holland

If you like old industrial sites, then a stop at the Landschaftpark in Duisburg would be worthwhile. It will be a minor detour for you on the way to Düsseldorf. I was there in October last year and enjoyed it.

Menno