The version 1.5.0 now includes a dropdown selector for choosing the delimiter character before doing the export. Try selecting comma, semicolon and tab to determine which is the preferred separator by your version of Excel.

Each form has dedicated storage settings under the “Storage” tab to exclude form fields from the CSV export:

We’re currently working on a simple interface to toggle the capture in form settings. However, that feature is still in the development. Therefore, you need to use a PHP filter in the functions.php of your theme to do this:

// Capture submissions only for specific form IDs.
add_filter( 'cf7_storage_skip_capture', function( $skip, $form ) {
    $capture_form_ids = array(
        12,
        23,
        34,
    );

    if ( ! in_array( $form->id(), $capture_form_ids ) ) {
        $skip = true;
    }

    return $skip;
}, 10, 2 );