1966 coupe, with the 200 sprint, because that was the car I bought when I was 16 (although I didn't get to drive it until I was 17, because I had to fix it up).
I'm a bit to young to have been driving the original mustangs but I am a Ford guy. If I were to get a mustang it would have to be manual no doubt. The 302 Boss has always appealed to me. I typically don't buy flashy stuff but in the case of the mustang I would go all out with the classic baby blue with black stripes or orange/red with black stripes.