Russell's paradox dilemma

Hi,

I have a problem with "Russell's paradox" which I have just learned about at school. Simply said, it means that:

Let's say we have sets *R* and **A**. And according to Russell's paradox (or theory) there cannot exist such set **R**, that:

But I think that such set "**exist**"...

What exactly means that ? Then the set **A** could be one of these:

And what means that ? Then the set **A** could be one of these:

So let's say that .

Then:

...so **I have found** such set **R** that:

So where is the paradox (Thinking) ?

Thanks.