Note: I should probably mention that this addon (and in fact, most of my addons) has been abandoned at this point. That is to say, I don't maintain them, and there are possibly bugs in them.
This is a very simple addon, with two parts. In the .rar archive there's two folders, AutoLootOn, and AutoLootOff. You just need to extract (or enable ONE) of them and the interface option, AutoLoot (loots all items when opening an object/corpse) will be set to the corresponding value (on/off) whenever you log in.
Doesn't have very much use, but may be useful if you share an account with a minor, or a similar situation.
The interface version in the ToC file is set to 30200, so it will show up as out of date. I think the newest interface version is 30300, so just set it to that in the Toc file(s) if you want it to be recognised as not out of date.