Does embedding c++ code in python using ctypes, boost.python, etc make your python application faster?
Suppose I am making an application in pygtk and I need some functions which need to be fast. So if I use c++ for certain tasks in my application will it be beneficial? 
And what are other options to make python code faster?
It depends, there's not a definitive answer. If you write bad code in C++ it could be even slower than well written Python code.
Assuming that you can write good quality C++ code, you can expect speedups up to 20x in the performance critical parts.
As the other answer says, NumPy is a good option for numerical bottlenecks (if you think in matrix operations rather than loops!); and SciPy comes with weaver, that allows you to embed inline C++ and other goodies.
Does embedding c++ code in python make your python application faster?