Vista - dot-net, C++/STL, interoperability, standards conformance

My experience with programming is mostly C++/STL interfacing with
Matlab for scientific algorithms in a Solaris environment. No GUI
development experience at all. I've found that it takes quite an
investment of effort and time to learn about, and judiciously use,
best practices and idioms in order to really benefit from a language,
library, and or development environment.

These days, I am using mostly Visio and Excel, stumbling along with VB
without formal training. Mostly trial/error/cut/paste on VB, and
tripping all over the place -- not for lack of concepts, but because
of missing details such as syntax and idioms e.g. for interfacing VB
to the application's memory/workspace, and how to access things in the
application from the program code.

Despite lack of time to learn the development environment from the
ground up, and incessant overriding of course-taking opportunities by
short term deadlines, I will push for a precious hiaitus to learn all
the i-dotting and t-crossing so that I can operate in the Microsoft
environment. Then I got thinking...I've read that dot-net allows one
to leverage experience from all sorts of languages...why strike out on
yet another language (VB) if I could leverage C++/STL??

The only thing is, C++/STL is not a microsoft language, so I'm
wondering how well it is supported in dot-net. It is one thing to say
that dot-net allows "interoperability" in concept, but we all know
that standards conformance and support of functionality requires
constant hypervigilance, both in terms of the supporter, and keeping
abreast of the supportee. It only takes a little bit of
nonconformance, or incomplete support of functionality, in key areas
to make "interoperability" more theoretical and practical. Can anyone
comment on conformance and support in the dot-net environment, as well
as good, accessible, and easily navigatable documentation?

Another potential pitful that I'm trying to get visibility into (or
allay concerns about) arise from the fact that VB is ubiquitous in the
Microsoft environment. You pretty well can resort to VB to add
functionality to any application (even though I am still figuring out
how to access the workspace of that environment from the code
itself). How complete is C++/STL interface to applications
environments, and associated documentation? Is there any handicap in
using C++/STL to add functionality to applications compared to VB?
Part of the answer to this may be related to the fact the C++/STL is
compiled rather than interpretted, though I'm not sure whether this
gives rise to any disadvantages.

Finally, how good has Microsoft's track record in keeping maintaining
interoperability and applications interfaces as dot-net evolves, and
even as C++/STL standards evolve?

Note that I'm not sure whether dot-net is even available in the
computing environments that I work in now. Some of the key
environments do not permit much flexibility in what can be installed.
This post is more of an advanced scouting.

Thanks.