Have you looked at multiblogs.php? This will do exactly what you want...

Or if you only want a list of your blogs and the last post titles, have the index.php call summary.php

The blogs/index.php will call other pages. The default is [ta-da] default.php and that is what you see as the first page of the demo or the first page of your site if you don't change anything. It can call a specific blog to be your first page, and you can set defaults (such as the skin) for the presentation of that blog as the first page. The index.php can also call a special blog, known as the "All Blog" that aggregates all of the blogs onto one page or another special blog, the "MultiBlog". In addition, it can call summary.php.

In index.php change the last of the "if empty" clauses from...

if( empty($blog) )
{       // No specific blog to be displayed:
        // we are going to display the default page:
        require dirname(__FILE__).'/default.php';
        exit();
}

to...

if( empty($blog) )
{       // No specific blog to be displayed:
        // we are going to display the default page:
        require dirname(__FILE__).'/summary.php';
        exit();
}

You can then manipulate the summary.php to match your site style.