Is there a difference between these two statements inside a function?
bool returnValue = true;
// Code that does something
return(returnValue);
They are identical. I see the parenthesis syntax quite often, and I always ask those who use it: why? And none can answer why they use it.
To bluntly sum it up, parenthesis around returning expressions are used by people who don't quite grasp the difference between function-like macros and functions, or who are confused about the operator precedence or order of evaluation rules in C. There is no coding style benefit from using parenthesis.
Thus
return value;
is more correct than
return (value)
because the latter suggests you don't quite know what you are doing :)