1. Top 10 software skills in advertisements:
( See below about C. I think that is still in demand because of the number of existing applications that use it, but not for new applications. )
My recommendation is C#.
This might be a bit basic, but here's a book for beginners, maybe you could skim it if you find it easy:
Programming in the Key of C#: A Primer for Aspiring Programmers
by Charles Petzold
'Compose your first software applications with programming maestro Charles Petzold.'
You can get a free development environment here for Windows:
C# is pretty much the only development platform for Microsoft Windows Desktop and Web Servers.
Don't do these, you'd be wasting your time:
Pascal: barely used in industry now. Used to be used as an educational tool
C, C++: not used for new development except in niche applications, there are already many skilled developers to fill those jobs; these two languages, especially C++, are more complicated than C#, and you could easily get lost, in fact that is why C++ is not used so much now - it's way too complicated! C# is a sensible simplification and is much more powerful. You don't need to learn C or C++ before you learn C#. Just go straight for C#.
Visual Basic: A Microsoft competitor for C#, but nearly all serious programmers use C#. Not worth it if you can use C#.
Others you could consider:
Java: a very serious language, shoulder-to-shoulder with C#, based on Unix or Linux more than Windows.
Python/Perl: Only if you're just scripting, but want something more powerful
In summary, C# is Microsoft's strategic language for the next 10 years, at least, I would guess. It has one main development environment ( Visual Studio on Windows ) whereas with Java, there are a potentially confusing array of environments.
You should learn a database as well: if you're going the C# route, use Microsoft's SQL Server, there is a free version:
At the end of the day, you have to make your own decision, and what I recommend based on my experience may not be suitable for you.