Some ISPs are introducing a service that automatically tunnels your traffic to a PPTP server on a remote network. (Your ISP will be able to tell you whether this service is available.)
You can use Dial-Up Networking to make a connection to a PPTP server across the Internet if your ISP provides a PPTP service. You do this by using Dial-Up Networking and your modem or ISDN device to connect to your ISP server. You do not need to define a VPN connection because the ISP server makes the connection to the PPTP server for the PPP client.
Contact your ISP to find out whether they have a PPTP server that provides a PPTP service and, if so, how to connect to that server.