Potential Router problem trying to set up Web Server

Hey all

I'm trying to help a web-designer friend of mine set up a web-server,
and running into problems

Win XP, PPPoE connection, SpeedStream modem/router combo

Apache was obviously the server of choice.
He doesn't have a domain name registered, so we decided we would use
dyndns.org to set up a subdomain.

Apache installed fine...
we can route to http://localhost and get the defaul page
It Works!

configured the modem/router to use dyndns.
dyndns.org is showing the proper WAN IP Address when we login to his
profile page

2 problems though:

A)
I'm used to using a Linksys router...
they have an option called
"Filter Internet NAT Redirection"
with this option off, I'm able to access my webserver at home
remotely... over port 80.
I can't find any similar options within his modem/router's GUI
so even after trying to forward ports from port 80 TCP to his
computer's NIC...
we still got prompted to login to his router!

B)
when I go to his command prompt (XP)
and try to tracert to his dyndns subdomain
it times out, and ... the IP Address that it lists is different than
his WAN IP Address

Any advice anyone can offer is more than welcome
Thank you in advance!!!!