Do not leave the hook in the fish.
There is a page on the forum here that shows you how to remove a hook that is deep.
In simple terms reach your fingers through the gills and turn the round bend up by pointing the eyelet down. THis will expose the round part and just pull it straight out with a pair of pliers. Very simple to do, very clean and I have yet to hurt a fish doing this. Just make sure you dont damage they gills.
I found it. Works awsome
http://www.in-fisherman.com/magazine/articles/if2806_HookRemoval/index.html