VB.NET and C# perform as well; they both get reduced to similar intermediate language, which gets run on the .NET.
The reason to learn C++ is primarily because it is the dominant language of the game industry. Also, it is a lower-level language than C#/VB. With that comes more flexibility, power and fine-grained control at the expense of ease of use, learning curve and maintainability.
Eventually, if you continue to learn the field of software development, you will (hopefully) know more than one language; C#, C++, Python, C and some assembly will be the likeliest ones you'll encounter.
As for hiring, your challenge is that you seem to be ready to flood yourself with too much new stuff and burn out like a shooting star. Secondarily, not knowing how to code means not knowing a good coder from a bad one. Not a huge issue, but one to think about as you layer challenge over challenge.
Anyways, get a book on game development, and read up on the field. Make sure you want to do this, as it is much more challenging a field than configuring a shopping cart.