Well this question is useful because many use WordPress but want instead the classic blog a standard welcome or description page. This is a static front page or a splash page. There is a very good tutorial in the WordPress site. See it from here.
Well nowadays WordPress supports this feature by default.
To set a static page go to the administration then look on the menu for Settings->Reading and change the front page display settings (see picture for example).
If you have questions too don’t hesitate to ask me.