Car and Key Settings Explained
Automatic Locking Key, when enabled, will auto-lock all the doors once you reach 5 mph.
Selective Control Unlocking Key, when enabled, will open only the driver's door when the open button in pressed the first time. All the other doors will open when the open button is pressed a second time. With this feature disabled, all the doors will open the first time the open button is pressed.
Here is a good, detailed list for the car and key settings I found on the Net:
http://www.bmwnation.com/home.html. Once on the website, click Tech --> Tech Glossary --> Car and Key Configuration Options - 3 Series E46