Jag running rough

I believe it is common for jags to leak from the hoses coming in from the railing. I had the same problem; I saw some gasoline pooling near the intake but also saw a wet hose. So I tightened it, and then read up on it. Found out. It happens. So always keep a screwdriver in your car. About the rough idle. It is also something that i'm always batlling with. So far, I can make her idle on Park/Neutral at 700-800rpms. Achieving this with the "idle SPEED screw". But when I pull it into Drive, she has fits about it.
So then I go to the idle MIXTURE screw (that, for some reason, no one dares mention)
and when I screw it in all the way. The car keeps running, which boggles me (car shakes but stays on). I notice that if I only unscrew it 1 or 1.1/2 turns out. It idles better. But I don't know this to be a good thing.