I also had the same problem where the service won't stop. Here's what I did:
0) If you click 'driver details' from the 'driver' tab of the device properties (from device manager), it will show you the driver name and location. It should be C:\Windows\System32\Drivers\vwififlt.sys
1) Get a valid copy of the driver (vwififlt.sys). I have another computer running the exact same version of Windows 7, so I copied it from the system files of that computer.
2) Restart the computer in safe mode. This ensures that the service won't be running.
3) Follow these
instructions to give yourself rights to delete the driver.
4)Delete it, and replace it with the valid version.
4) Restart normally.