He just means he's appointing himself a "Captain" and leading...
Other than that the references have nothing in common.
Captain Crunch is a character on (or the name of) a US breakfast cereal box.
Captain Kangaroo is an American children's television series that aired weekday mornings on the American television network CBS for nearly 30 years, from October 3, 1955, until December 8, 1984.
There was no actual kangaroo in the show..
(the name "kangaroo" came from the big pockets in his coat)