Router Problem

[MGSolidSnake5]

I'm pretty sure that this question has been asked plenty of times, cause I was searching the forums and looking for answers. I found some help, but not enough. Download the pic I attached to see what I did. I got a Linksys router BEFSR41. My ISP does not use Static IP. Now I used to get this:

<06/10/03@14:49:54> [yp_add] yp.shoutcast.com gave error (nak)
<06/10/03@14:49:54> [yp_add] yp.shoutcast.com gave extended error (Cannot see your station/computer (IP: 24.185.38.201:8000) from the Internet, disable Internet Sharing/NAT/firewall/ISP cache (Connection timed out))

What I did in the pic fixed that problem. Now I connected to my own station and it worked great. Then I asked my friends to check it out, and they got the "DNS Error" or whatever. What's wrong?