The first screen shows the archive content and allows you to select which files and items you want to restore. A checked item means that the item is selected with all its contents, the empty check box means that the item will not be restored. A gray check box means that some but not all of the item's contents have been selected. If you want to restore the whole archive then make sure the top level item (archive title) is checked.

When you finished selecting the items click Next to continue.