C and C++ are related in such a way that C is a subset of C++, meaning that a program written in C should compile also using a C++ compiler. They share the same basic syntax with C++ having a number of additions over C, but most of programming IS basic syntax, so if you learn C++ you definitely learn C as well.
For ease of learning, though, I would recommend Java. The basic syntax is still the same as C, but you don't have to worry about memory management, pointers etc. and you'll learn objective oriented programming. Just make sure you don't get stuck on Java, learn the basics there and then move on to C or C++ (or even objective-C if you'd like to try OS X or iPhone programming). Learning just Java will lead to some poor coding habits, so it's good to move to the C-family to see what is going on under the hood, so to speak.
So, in a nutshell: Java, C++ and objective-C all have the same basic syntax that is based on C.
