Compiler - Microsoft Visual

In your opinion: What is best Microsoft Visual C++ 6.0 or the 2005?

2005 if you are looking for a quicker and more standards compliant compiler. 6.0 if you are looking to work on legacy code

2005, because it goes with the standards. Judging by the question, you are still learning the language (we are always still learning it, but in this case I mean getting used to the basics) so learning in a standards compliant compiler will help you more down the road.