Welcome to the Germansection of the forums for self hosted WordPress blogs.
While we prefer to speak in our native language here, I’ll try to give you an answer.
Usually you should see two URL’s in settings > general, site_url which points to the URL that is used to view your website and wordpress_url being the address where your WordPress core files are stored. Both values can be individually set if they don’t get predefined in wp-config.php by adding
define( 'WP_SITEURL', 'http://example.com/wordpress' ); and
define( 'WP_HOME', 'http://example.com/wordpress' ) respectively.
Those settings of course only occur on selfhosted blogs. If you run your website with WordPress.com, you will have no chance to alter those values, as everything has been arranged for you already.
Hope that helps. If not, feel free to drop a note.
