I have the VLC player on both my notebook and desktop.
This thing about DVD drives on computers... they only allow 4-5 region code switches... upon which the DVD drive would be "locked on" to that region code.
You might take a look here to see if they have anything that can help you.
Remember, if you aren't sure what you're doing, you could end up buying a new drive, as the old one could end up non-functional. Various companies have made it difficult to remove the region coding, so not all drives will have a solution.