If you want someone who has some passion for the game, then Ian Wright is the man, if you want a footballer with a few brain cells, then Clark Carlisle is the man.
If you want someone who cannot engage their brain before they open their over lippy gob, have less intelligence than the average tadpole and the memory of a gold fish, then I suppose there is only Rio Ferdinand, the same Rio Ferdinand that threw his toys out the pram when he wasn't selected to play for England and then got a dodgy back but still managed to fly off to the far East for a commentary job.