Hi, Nikky
I have made some of the entries clearer in the original post.
As regards the Sukkulentensammlung, that encompasses all plants that can store water for a longer period of drought, such as the cactus or the Aloe. The collection is inside, and I have not been ther yet, but apparently, they have some rather rare plant. Every now and then, I have read that a special cactus is blooming for a day or two and that one should go to see that. The collection is not too far from the Zurich Main Station.
The museums I listed are also listed on the page
http://www.zueri.ch/d/mus001.htm, where you can also find opening hours.
Hope that helps
Idgie