Schumacher has 7 world titles. he also has 91 wins in 250 career starts. he has 154 podium finishes (1-3). he has a winning percentage of 36 percent. he was on the podium 61 perecent of the races he started. of his podium finishes, 91 were wins therefore, when he was on the podium, 60 percent of the time it was because he won. compare that to 200 wins in 1184 (16%) for Richard Petty. Dale Sr. only had what, 76 wins.
impressive when you consider the average F1 season in about half that of a NACSAR season.
Mario Andretti is the only race car driver to win the Indy 500, the Daytona 500 and an F1 World Championship. he has also won 4 CART championships. he also had many more Indy 500s on lockdown before some sort of mechanical failure put him out.
while the accomplishments of Petty and Dale Sr. are certainly amirable within their sport, saticstically, Schumacher was the greatest race car driver ever. Andretti was probably the most diversified race car driver, followed closely by Emerson Fittapaldi and AJ Foyt.
one could also not make an arguement for best race car driver without also considering Rick Mears, Al Unser Sr., Jeff Gordon, and Tony Stewart. the only thing missing from the latter two's resume would be a Borg Warner Trophy to add to their collection. unfortunantley, when Smoke drove in the IRL, he drove for the most snake bitten team in all of motorsports or else he would have one right now. Smoke did manage to win an IRL title.