A.D.
If you don't mind spending a little bit of $$ - get one of those musical toothbrushes (called Toothtunes). They cost about $10.
It worked amazingly well for my kids!!
We got a Beach Boys one for my son - he fought me at first (like normal) but as soon as the brush hit his teeth and "Fun, Fun, Fun" started playing in his mouth... well... now he begs me to brush his teeth!!!!!
My daughter got a Hannah Montana one and we got a Smash Mouth "All Star" for my 2 year old. They have a TON of different songs!
You can buy them at any store - or go to their website if you are looking for a specific song: http://www.hasbro.com/toothtunes/default.cfm?page=Product...
Good Luck in whatever you decide to do!