Okay here are some screen shots to show you what your settings should look like. obvious th excact settings from your ISp will be different, and I'm shring my school's wireless connection with my mac, but it's the same diffeance. I hope I've been some help.
http://homepage.mac.com/kearnet/PhotoAlbum5.html
http://homepage.mac.com/kearnet/PhotoAlbum5.html