Make the blog private and set private pages

Hello, with this idea in mind, I have matched to reorganize my word press site a little ( Thanks to MichaelH ?? ! ).

But I have 2 problems :

1) I’d like to make some pages private and to rule users groups, so I have installed a plugin named Group Restriction. It’s supposed to say what users group can or one page or not, to read it or write on it. It works only for normal pages.

2) When I try to make my blog unreachable whith this plugin, it doesn’t work. But only for the blog page. So I have made the blog page a bound on another page which I made private.

But the URL is still fully accessible if you add this : ?page_id=669

Which is the varaible and the name of the page. so the content (thes pots on the blog) are not private.

How can I do ? ??

PS :

I suppose I can made posts private one by one, but Id like all the page would be unreachable except by members.