If you're just learning, make sure you have "stall limiter" disabled in the flight options. Trust me, better to learn now, than to re-learn later. It's a huge crutch. Play around with it to see what it does, but disable it when you want to get serious.
I disagree with "pick a plane and learn it". If you're starting out, pick an easy plane. Just don't rely on that plane from now to eternity! Use it to learn, but once you're able to fly a sortie without crashing move around to other planes. Good "easy mode" planes include spit 16, spit 8, spit9 and spit 5, as well as LA7s, Hurricane Mk.IICs, and some others. P51D is a decent learning plane, but won't turn very well at first (that comes later, with experience).
If you start in a spit, for god's sake don't fly it exclusively. Don't always take the face shot then run (those planes turn great, too! Don't forget!), and don't get too cocky if you start getting kills because chances are you're pulling moves in a spit that you cannot pull in any other plane.
