From the newly released NewsCorp quartly earnings report for the period ending March 31st:
In total all of NewsCorp had a net profit increase of 69% to $465.000.000. They sadly don't give numbers regarding the DVD sales but for some reason, the two non-cancelled animated shows got no mention. A quick check on amazon shows that King of the Hill has abysmal sales and Futurama beats The Simpsons on a season by season comparision. Keep in mind that The Simpsons' releases are about a year older. Family Guy again beats them all.
Twentieth Century Fox Television (TCFTV) profits continued to expand, primarily reflecting sustained momentum in home entertainment sales, most notably from Angel, Futurama, Family Guy and 24.