If there is a glitch like you're experiencing, try updating your drivers first using your manufacturers update assistant.
For example, HP use the HP Support Assistant. From there you should be able to easily find your drivers that are outdated and need updating.
If you don't have your manufacturers installed "assistant" software, then follow these steps to get yours.
Go to your computer manufacturers website, select support tab.
In the support tab you will see a driver download section - Click onto it and the server will begin to scan your system for what is currently on there and what should be and reccomend a fix for you.
That should delete the magix driver for you. If not then go to your device manager, and update the driver manually.
Start ===> Control Panel ===> Hardware and Sound ===> Device Manager
And then you can update or delete the driver from there.
Are you aware this thread is more than 18 months old? Since the OP has not apparently logged into the forum since making his one and only post, I very much doubt whether he is still interested.
However, as you write, your method will disable but not uninstall the unwanted driver; I suspect the solution offered by martinheeremans is actually the best.