They will always drop dragon bones and green dragon hide. They also drop a variety of other items, none of which is particularly valuable - such as runes, herbs, some armour and weapons.If this is for a slayer task, you can also kill brutal green dragons instead.
there are no baby green dragons
Currently, Baby Green Dragons do not exist in the game.
You are a wizard.
lvl 79
Mithril dragons have a 50% green charm drop rate, dropping four charms each time, which is by far the best. All dragons in general have a fairly good green charm drop rate. The higher level the dragon is, the better change of getting charms. Level 96 cave bugs have an excellent drop rate...considering how weak they are. Cave bugs can be almost as good as mithril dragons, but cave bugs only drop one green charm each time as opposed to the mithril dragons four charm drop each time.
yes
no, they cant even fight green dragons.
They are just east of clan wars
I presume you was referring to the Draconic Visage. It drops from most if not all dragons. Mainly Black dragons and metal dragons most.
Blue dragonhide, dragon bones, sometimes coins, etc.
If you are talking about runescape then no, water dragons don't turn green ever. :) :P yours sincerely Winner1
If you have never killed a dragon before I would suggest killing green dragons. They can be found east of clan wars in about lv 23 wild. They drop green dragon hides and dragon bones which together can be sold for about 7k, making them a pretty good way to earn money.