Take it from another noob, pick one[/b] aircraft and stick with it. My squadies told me to get out of the default p-51 and into something that will teach me how to fly. I picked the spit16 to learn in (not that I'm done...). I currently fly a spit9 or a yak-9u, depending on what I'm doing. I happen to like turn fighting over boom-n-zoom'ing. Some prefer bnz over turn fighting.
Every plane has it's strengths and weaknesses over another plane. My spit9 can't chase down most other planes, but I can outturn just about anything but a good nik or ki pilot. I can probably catch and outturn just about anything in my yak, but once I catch them, I have cannon ammo conservation problems.
Again, pick a plane and stick with it.