Apart from the obvious difference in syntax, the two languages are pretty
much identical, apart from a few areas:
- C# supports pointers, VB.NET doesn't
- C# is case-sensitive, VB.NET (generally) isn't
- VB.NET permits sloppy coding (!) by turning off Option Strict
Plus a few minor other differences...
Ah, but that's a very different argument...

You've posted in a C#
newsgroup, so most people here will applaud your wishes. However, even if
you have a huge investment in VB6, please don't let that influence your
choice of .NET language. One of the biggest mistakes people make is to
imagine that VB.NET is the next version of Visual Basic - it isn't - not
even close...
All of the above can be done equally well in C# or VB.NET. For virtually
every aspect of programming against the .NET Framework, the actual
programming language is irrelevant because they all compile down to the same
thing anyway...
I would advise you to take a modular approach based on the seven core
modules as outlined in the Microsoft Enterprise Library:
http://aspnet.4guysfromrolla.com/articles/022305-1.aspx, and develop
reusable base classes for each of these. I'd further advise you to start
with a database abstraction layer (DAL), because database connectivity is
pretty much fundamental to any business software development.
Doing this will not only give you a lot of exposure to the most important
areas of the .NET Framework, but it will also vastly simplify the rest of
your development tasks.