Can't you people see that the
names are
almost the same? They've gotta be compatible, and migration has gotta be easy, right? I mean, why would they name them so similarly if it wasn't?

Yes, the family of .NET-capable languages all have a learning curve, and from what I've read VB was probably the worst off - they not only changed syntax and overall code structure, they also deprecated parts of the previous API and fundamentally changed the functionality of other parts of it. In general there is no migration path for a VB6 application, but if you have VB developers already it does provide you the option to retrain them for
new development in VB.NET.
AFAIK, C has been left out of the .NET family, but C++ made it as "Managed C++". You'll need someone more knowledgeable to tell you what that means, though!