If your cat shys away from hard food, she may have gum disease or another problem with her mouth. Check with your veterinarian. A cat will often knead against a favorite spot when she is content. This is a throwback to kittenhood, when kittens knead against their Mother to stimulate the flow of milk. Shots are an absolute necessary precautionary measure for the health of your cat.
Shots immunize cats against lethal viruses and diseases.
Indoor cats are exposed to visitors and strangers more than indoor-outdoor cats, and usually handle people a bit better. Some shy cats still run and hide, but most are right there to investigate the newcomer. This is a very personal matter. I would need to know if the cat will be kept indoors, how many members of the family are there. On one level or two.