@Oleg:
I respect your opinion, but his McLaren in 93 sucked. Why? Because it didn't present any step forward towards other McLarens, few other cars on the grid were vastly superior (especially that beauty called Williams). Senna said that HIMSELF. Nobody in the world can argue with a driver's comments, not even the car engineer. Especially when the driver is called Ayrton Senna. Schumi's car was a beauty too.
To do what he did with that car is a miracle and display of magnificence. This is a fact. Go look for Senna's information and stuff. You'll see.
Back to who's best, I stand with my previous opinion. Senna first, Clark second, Piquet, Fittipaldi, Fangio, Villeneuve, Lauda, Stewart, Prost, and after many more (including people who never won), comes Schumacher.