FYI, just got a SCH-a930. If you want to use Bluetooth instead of the USB cable to get internet on your PC, here's what you do:
1. Go to MENU
2. Select SETTINGS & TOOLS
3. Press #
4. Enter all zeros for the password
5. Press 4 to select Port Map
6. Press 1 to select DS (DATA)
7. Press 3 to select BLUETOOTH
You should now be able to use your phone as a bluetooth modem. When I paired my a930 to my Mac using the bluetooth system preferences panel, at first it told me there were no services for me to configure. After I turned this on I was able to configure it as a modem.
If you want to switch back to using the USB cable, just go back to the menu above and press 2 to select USB.