I'm thinking about unrooting and going back to completely stock, vanilla Android on my Droid.
How can I do this?
This is a stab in the dark, that I read somewhere else:
I'd be interested to find out how this works after the phone has been rooted.
This code is used for factory format. It'll remove all files and settings including the internal memory storage. It'll also reinstall the phone firmware, which should remove your root!
Once you give this code, there is no way to cancel the operation unless you remove the battery from the phone. So think twice before giving this code.
Enter this: *2767*3855#
in the dialer.
This website has a very good answer: http://www.droidforums.net/forum/droid-hacks/13466-how-back-stock-no-su-no-busybox-etc.html
Seems to cover all your bases.
Good luck :)