troubling configuring wireless nic

[Terrence Wilson]

This is my first time experimenting with FreeBSD and UNIX-based systems 
in general. I am trying to configure a wireless nic on my laptop, which 
is a windows-free bsd dual boot system. 

At home, I can access the internet in Windows through a router which 
also connects my destop (a windows xp machine) to my internet cable 
connection. When in FreeBSD, I run ifconfig and it indicates that the 
nic is running and gives its inet address, one which is different from 
the ip address given in windows. When I ping the address given by 
ifconfig, it shows a connection. When I ping the the gateway given for 
the windows machines (the ip address of the router) I get nothing in 
FreedBSD. 

So, I edited the /etc/hosts file. I entered the windows ip address for 
the router into the /etc/hosts file as the local host. Then I edited 
/etc/rc.config file to assign the ip address given in windows to the 
inet address of the nic. When I save the files and reboot, I get this 
message which repeats itself several times:
"login : Sep 4 11:24:49 sm--mta[561]: NOQUEUE : SYSERR(root): 
opendaemonsocket: daemon0: cannot bind: can't assign requested address
Sep 4 11:29:37 sm-mta[561]: daemon Daemon0: problem creating SMTP 
socket"

After this message flashes at boot up, I login as root and try to check 
the etc/rc.config file but the system responds: "Permission denied".
when I run vi on  /etc/config, it opens as a blank file.

What do I need to do different?