D-Link 804HV

I am trying to set up a VPN connection from Win XP pro to an 804HV. I have set up the PPTP link and it connects to the box. I can only ping one of the computers on the LAN side of the 804. I get no reply from them. If I go to a computer on the LAN side I can ping all computers with no problem. Can somebody please tell me if I need to set up a VPN connection with IKE and IPsec as well as the PPTP or should I be able to see all my Lan network from the XP client.If possible answers to this are much appreciated.