Answer #1 - Sometimes, teeth just take longer to fall out in our Yorkies-"Small Breeds". It is also common for Yorkies-"Small Breeds" to retain some of their baby teeth and later, they should be extracted. Vets usually do the extractions when the puppy is undergoing their spaying or neutering.
Answer #2 - I would not be too concerned about the trash can...Is is the trash bin or the noise that is upsetting her? I would assume that she would get use to it after a while but I know many don't ever get use to the things that "bother" them. Sorry I do not have much advice on this. I am sure someone on here will have some great pointers for you.
Answer #3 - Many Yorkies are picky eaters. Mine like to pick up a few kibbles at a time and take them to where they would like to eat-be it the carpet, the bed, on the couch or right by the bowl. I do however, put the food in their bowl, I would try to give it to her in the bowl. Wish I had more advice for you...
Answer #4 - Here are two links right here on YT about food, the first one is Dangerous Foods
http://www.yorkietalk.com/forums/showthread.php?t=43555 , the second is Poisonous Foods
http://www.yorkietalk.com/forums/showthread.php?t=35792
Good luck...
