Hi and Welcome to Fishlore!!
I'll try to answer your questions with as much as I know. I'm sure others will provide additional information and/or correct me if I've given some incorrect info.
First and foremost, you must pay attention to the adult size of the shark with regard to the size of your aquarium and get one that fits within those parameters. You also need to recognize that sharks tend to be on the aggressive side and unless they are kept in very large tanks, only one should be kept in a community tank. This is because they are territorial and may attack other fish that they perceive to be invading their turf.
You should also be very aware of what tank mates would blend well with sharks. Since most tend to be nippers, it may not be wise to keep any fish with long, flowing fins as they may make prime targets for the shark's aggression. And some just don't make good tank mates.
I couldn't really make out the rest of your post, but I think it referred to breeding fish. Livebearers such as guppies, platys, mollys and swordtails are all very easy to breed. Some may be compatible with sharks, some may not.
Here is a compatibility chart that might give you an idea as to what will be compatible in a community tank.
http://www.liveaquaria.com/general/f...lity_chart.cfm
Happy research and good luck!