The whole idea of selecting just one is wrong. To understand things you really need to know several languages, and also you need to learn programming, something which goes beyond languages. Also, by many reasons it's better to start with C# rather than VB.NET. I explained it in my recent answer:
From QBASIC to Contemporary Programming Languages.[
^]. Please take a look at the whole discussion.
Also, it's very hard to advise something, but I can explain the problem. Many developers are really haunted by the problem of imprinting. Many develop strong bonding to their first favorite language so much, that it blocks their ability to perceive alternative ideas. Try to avoid it, hard to explain how. Use your brain and critical thinking, not the feel of comfort. You need to avoid such thing as sitting in a "comfort zone".
—SA