What version of C++ is good ?

I am currently using VC++ 2008 Express Edition.

As I have understand this is non-standard and therefor other versions of

C++ could be a better choice.

What I wonder is, what version of C++ is a better alternative.

To keep in mind is that I need a version that reads .txt files and do Very fast calculations on these and on Arrays as I am very depending of that.

VC++ 2008 does fast calculations and from what I understand C# is a bit slower on that part and calculations on Arrays.

I would also be happy to use C# 2008 Express Edition if it really is that fast in calculations as the VC++ 2008 Express Edition.

So I need a combination of Windows Form Application and fast Calculations.

Thanks in advance !