I'd say C# because it is closer to JavaScript which is perhaps the most popular language in the world at the moment. It is also similar to many other popular languages such as Java as used on the Android OS and Object C as used on the iPhone.  

Visual Basic is slightly easier to read but frankly if you want to make software that actually matters it isn't that useful as either a learning exercise or as a programming language. 

Nothing of value is written in Visual Basic.