If you are familiar with C/C++ I would recommend C#. It's not important whether you chose VB or C# both are compiled to MSIL so the end result is the same. Therefore, I think you will pick up .NET programming quicker if you go with C# because you will spend less time getting used to the syntax and have more time for learning the .NET framework and all it's classes.
Just google 'Getting Started With .NET" to get lots of great resources.
is an example.
msdn2.microsoft.com is the official developer centre for all things .NET.