FactCheck.org provides a helpful reminder that almost every chain email about a politician (usually a Democrat) is utterly false. If there were chain emails about John McCain they'd probably be false too, but most of the emails focus on Obama or Clinton.
No, Barack Obama is not a radical Muslim. Nor does he want to change the national anthem. And no, the Clintons did not charge rent to Secret Service agents. They also aren't murdering their opponents. And just for good measure, freezing a water bottle won't give you cancer.