Using a C/C++ library in .NetFramework

Hi i am new to .Net
i am trying to develop a mobile application and was evaluating to use .Net framework for that.
i have few questions for the gurus:
1. what is the best language that i can use for this.
2. is there any difference between the regular C++ and the C++ that we have to use in the .Net framework.
3. the application that i would develop has to use a Libs which are written in c,c++. can i include the header files and invoke this apis?

thanks in advance,
KU.M