I recently visited Kodaikkanal with my family. I engaged a driver named Abbas who runs a cab company called Masha Alla cabs. He not only took us to every nook and corner of Kodaikkanal, but acted like a guide to us at no extra charge explaining every bit of details. The guy hails from Kodai and hence has indepth authentic knowledge about it. He was also friendly and patient with us which is rather more important than anything else. And most importantly, he strikes a clear balance between being a friend and a taxi driver and doesn't indulge much into our personal space.
It was a lasting experience for us.
I suggest you seriously consider this guy if you happened to visit Kodaikkanal.
For your benefit, I am putting all the details here.