Doctor Who by loads
No.
The most popular animal in the world is dogs and dolphin.
the flaming moe was probably the most popular
'The Simpsons'
It wasn't the most popular series when this question was originally written nor is it today (09|2014). The Simpsons has never been the "most popular". The highest the show ever ranked was #21 for its 12th season.
Dr Julius Hibbert is the Simpsons family doctor.
In most cases, Dr Hibbert is the Simpsons' doctor. Occasionally, Dr Nick Riviera is involved.
Matt Smith has been claimed to be the most popular in the childrens program Doctor Who
According to a survey of Doctor Who fans the most popular Doctor Who episode was The End Of Time.
the most popular doctor who companions are Amelia Pond, Clara Oswald, and Rose Tyler
For kids... Probably Spongebob For Adults... Maybe on the lines of the Simpsons or Family Guy
The Simpsons have been popular for like 20 years, and Futurama has always been popular. So I would have to say both.