i can't get to the Internet !
 

i can log in to my ISP but when i launch my web browser & search for, say, www.google.com.. it says unknown host www.google.com...

why?

Login as user;
su - root
ifconfig ppp0
You should see two ip addresses.

Did you add you DNS server name for your ISP to /etc/resolv.conf?

if not
edit /etc/resolv.conf and add them somethng like this:

------------- /etc/resolv.conf -----------
serach you_isp.com
nameserver 111.111.111.111
nameserver 111.111.111.112