What is the right USB Charging Driver for the Droid

you dont need a driver to charge, only if you are debugging apps through your phone. You can mount your sdcard without drivers as well. Just look on your phone in the notifications and mount through there to see it on your pc desktop.

Your phone will charge if it's connected, regardless of any drivers or mounting.

If you need the usb drivers for debugging/whatever else:
USB Driver for Windows | Android Developers