wxWidgets is a graphical toolkit - a library - not a programming language. By default, the wxWidgets library is used through C++, but there are bindings to various other languages.
I heavily recommend Python, if you're just starting out on the programming front. And, whatever you do, I would suggest you avoid using RAD tools like BoaConstructor to build your interface: learn to write the code for generating the GUI yourself, by hand. Mind you though, there is nothing wrong with using BoaConstructor to model your interface, I just wouldn't recommend building your entire application in it.
PS. For what it's worth, I much prefer using PyGTK (
http://www.pygtk.org/).