Hi Denise,
It sounds like you are experiencing culture shock. I don't know what to tell you as to how to get over this. But I can tell you that staying inside will not make things better. Hanging around other expats who complain too much will also not make things better.
Suzhou is much safer than where I am from (the United States)... except for the trafic. People do not drive well here.
And yes, things may not be that sanitary...but at least most food is cooked with high-heat
It is likely someone was taking pictures of your kids because they think your kids are cute. Chinese people do that...alot. Its annoying, but you should try to have some understanding. Chinese are "kid-crazy". They just love kids and they think foreign kids are very cute. I have not heard of any foreign kid being kidnapped anywhere in China EVER. I think it would be too easy to catch the kidnappers.
Af for your Ayi, well...tough luck. You should not get a fresh, new Ayi. You should get someone who is local, who is recomended. Yes you need to search and search. But that is just they way it is.
I wish you best of luck and greater peace of mind.