Question 1) I think the whole propagenda about it being a starter drug is bs on the grounds that if kids were properly informed that in low doses, MJ is not nearly as harmful to you as more serious and addictive drugs like coke, Meth and so on then their wouldnt be as much intrest in trying out hardcore drugs. After all for most people who have tried it besides for some people making you sick afterwards it is nothing compared to how horrendous I remember them trying to make it sound in elementry school and have a few friends who did try harder stuff based on the mentality that since they lied about MJ they were probabaly lying about other drugs as well.
Obviously anything can be abused but used in low doses now and then i see nothing wrong with it, being used for medical and recriatonal purposes.
Question 2) Yes, making it illegal only helps get rid of it's allure to very young people as being cool and legalzing it and setting out guidlines for how much is ok to use before you need to start worrying about long term effects ( you have to be a pretty heavy smoker to become perma stoned though).
Question 3) Very Rarely, as in a few times a year at most, but not often and in small amounts no more then one joint sharing with a friend. I smoked from a friends bong once made me want to puke i was soo sick so never ever doing that again.
Question 4) I think 3 and 4 are the same no?