I have experience in socket programming in C, C++ and Python.
I am sure I'll be able to help you.
If you just need to work through telnet using sockets, I would definitively advise you to use Python.
Why? It is more flexible and easier to use than c++ or c. Working with strings (or bytearrays) is far more simple.
Of course, if you require high performance, then you need C++.