I am using the latest drivers with my 7970, and have no issues with AA in Skyrim. Where and how do you have your AA set?
Not sure what is up with Overdrive. Mine doesn't have those switches to enable - I just go to the overdrive page and place a checkmark to enable OD.
When you launch Skyrim, a Skyrim Launcher should pop up unless your using a different launcher.
You can go to options of the Skyrim launcher and set your graphics settings.