Depends on your goals, I suppose.

Over here in Europe, COBOL is still a big thing ( as well as most of the companies that use it). It's mostly used for legacy applications - business stuff...

C++ is used by a very small minority of the companies (technical copmanies mainly) - most of them hire engineers instead of programmers by the way.

As for VB: it only gets used for smaller projects as its platform is not considered to be very "reliable" compared to a mainframe.

When I started out 12 years ago, COBOL was the name of the game and - although I'm into newer things these days - it still is ...

I'd go for COBOL again, but would try to break into the newer technologies ASAP.

Cheers, MichaelD.