Basically, it depends on your budget. (Since this is a security site, I don't think it's a good thing to advise tp use illegal copies of software so I won't do that!) If you can't spend any cash, you will have to depend on freeware languages. Many of them are very good quality too.
Another thing to consider is the kind of applications you want to write. Do you want to build a back-end for a webserver? Some desktop tool? Games? Multi-tier database systems? System tools? Or something else?
http://en.wikipedia.org/wiki/Programming_Languages gives a good overview of all kind of programming languages. http://en.wikipedia.org/wiki/C_%28pr...ng_language%29 gives a nice overview of the C programming language. You can read there how C and C++ relate to one another.