I have done this process for a friend who has a AirTEl 512 kpbs connection like yours (dial up PPPoE). I first went through YaST-> DSL as I told you above, and entered the username and pass, and if I remember correctly the VPI/VCI too. After exiting the wizard, installed kinternet through YaST->Software management. Then opened a terminal, typed KInternet. The KInternet icon appeared near the clock. I right clicked on it to connect for the first time, browsed, tested, disconnected again by righ clicking on the icon and then closed the terminal window. There after KInternent comes near your system clock automatically at boot. You only have to right click and connect.
Enter your gateway as 192.168.1.1 in your network card properties.
Also read this
*www.swerdna.net.au/linhowtonic.html