#1
All right I'm having trouble with strings who don't stop ring, for exampel when I'm playing up and down on a scale the lowest string continues to ring and everythings just sounds like crap. Can it depend on the distance between the strings and the freetboard?
#2
I'm not sure I quite understand what you mean, but if I do, then you just need to mute the strings after they ring out the amount you want, it takes some getting used to, but try to barely touch the string thats ringing as you move down the the next string to stop it from vibrating.
#4
I don't see how what he/she likes to wear has got anything to do with it.

Anyways, 1fine69 is right you need to mute any string you're not using. This includes the one you've just picked, once you've allowed it to ring for the amount of time you actually want it to.

There are several techniques for doing it and different people use different techniques but the most common is using the palm or side of your picking hand.