It COULD be depending on what your intended use of the picture is.
well yay its illeagal
It depends on whether that person has a reasonable expectation of privacy or not. For instance if they are in a mall, yes. If they are in the bathroom at that mall, no.
no is illegal shame on you
Taking anything from someone else is considered stealing and is illegal, regardless of the fact that the stolen item is an illegal substance.
no it is not
No
it is illegal if you do not have the parents consent
Of course, unless the picture is of an illegal nature.
Yes, it is illegal to take a picture of someone's passport without their permission as it violates their privacy and can lead to identity theft or fraud.
No. There are no laws concerning matters like this since they are personal in nature.
No, as long as the person you're sending them to is not a minor.
If you don't have permission to use another person's picture from a site like facebook, then yes it would be illegal. If it is an already existing meme face such as troll face for example. It's so widespread in society and the internet that there is no way anyone will ever be able to do anything about it. Personal images on the other hand are more dangerous to mess around with without permission.