If you look for work, C# would be your primary chocice, closely following with java. C++ is far behind.
Now, depends what you want to write.
- For buisness aplications (for example any kind of calendar, home bugdget helper, chats, etc) I would recommend C# with dot.net.
- For games you need C++. C# and java are an option, but much more community help will come with c++.
- For mobile devices you will propably end up with Java. C++ is in some cases an option, but IMO it is not worth it.
- As for web, i have no much experience. You have actually to choose between java and C# . Limiting it to those two, I would choose C# - aspx and dot net looks a bit more newbie friendly.
This all comes with small assumption - you are working on Windows operating system.
Cheers,
Elrood