the op does not sound like he wants to remove the welcom box, it sounds as if he wants to remove the text from the top of the content container.

The only way I could see it being done would be to write a css for the site and omit a title from the box that way or change the text color for all of the box titles to mach the color of the box header so that it blends in.

I am no CSS guru, but I know that some of the sites I have visited here have done just what you are asking via CSS so that they could sub in grahics instead of the default text.

anyone with more CSS writing experience want to chime in?