I'm going to suggest something now that maybe not everyone will agree with...
If you're a WWII nut, or even vaguely familiar with the air war, and and there's a specific aircraft that you like, go for it. Don't worry about whats the best for beginners, what's fastest, what turns the tightest, what has the heaviest armament, etc.. Just fly the plane you like.
Flying Spitfires, Lavochkins, etc. at first is just going to handicap you and make it that much harder when you finally move on to the planes you really like. If you like, say, the P51, go for it, even though it's very tough to really fight in for beginners. I wish I would have just gone right to the 109 when I started instead of screwing around in 'teh bestest' planes for the first couple of months...
I heartily disagree. To think of a quick, perhaps cliche example, flying a good beginner plane is learning to walk, and flying a more difficult plane is walking a tightrope. Difficult planes simply require a better knowledge of this game's flight characteristics to enable the pilot to have any sort of success; you are walking the "tightrope", balancing on that fine line between combat performance in that aircraft, and loss of flight control.
Anybody would agree that learning to walk is a prerequisite for walking a tightrope- to saying anything else is silly. There's nothing to gain from trying to jump right on that tightrope...you simply do not have an understanding of balance yet.
Flying an easier plane is not going to teach you bad habits, it will teach you the physics of the game (the "balance" you need to even attempt that tightrope later).
Just my opinion.
Some good planes for starting off are the Spit VIII, Spit XVI, LA-7 (but please fight in it and not run from every fight you see)
When you start to understand the physics of the game world better, try new things.