DHCP Server for XP Home

I have recently acquired a broadband connection and wish to share with my family members. The ADSL modem is connected to a desktop pc running XP home. There are two more PCs, one running XP Home and the other running WinME. Both client machines are set to obtain IP automatically but the ip assigned to it is the 10.0.XX series instead of the 192.168.0.X series. Where can I check the DHCP server on the PC connected to the ADSL modem directly running XP Home? Any idea to my problem?