All the C languages are generally quite similar. C is not object oriented, though. (Note: you can write object oriented code in it, but it is not designed with the functionality in mind.)
Here's where it comes to opinion, though. I would always choose C++ over C unless absolutely necessary. C++ adds so much more to the language. Again, this is purely opinion.
Interestingly enough, these C languages are so often used for creating games because they don't need to run on anything more than the machine they were compiled for. Java, for example, is compiled to byte code which is run by a Java Virtual Machine...(written in C/C++ ) whereas C/C++ are compiled directly to machine code/assembly. As such, they have more direct access to the computer's hardware.
This is getting to be slightly too advanced for this learning forum, though.