"On Top of Spaghetti" is in the DT, credited to Tom Glaser.

The version of "Bingo" in the DT says you _mouth_ the missing letters. Heresy! You _clap_ for the missing letters! In my childhood the older kids (camp couselors) daringly sang, "There was a drummer had a drum, and Ringo was his name oh."

For a truly boring parody, there was always "Found a Peanut" (to the tune of Clementine):

Found a peanut, found a peanut,
Found a peanut just now.
Just now I found a peanut,
Found a peanut just now.

Cracked it open...

It was rotten...

Ate it anyway...

So I died...

Went to heaven...

Saw St. Peter...

(I think there's more--hell gets in there somewhere.)