Windows 7 or another Windows workstation class OS has no built-in DHCP server service role. If you want to run DHCP services on a Windows 7 computer, you would have to run a 3rd party DHCP application.
Alternatively, you an run a Windows server (or other server OS) as a VM guest on Windows 7 and install the DHCP role then bridge the VM guest's NIC to the host computer.
Depending on your DHCP/DNS needs, many networking "edge" devices can offer such services built in including a firewall. However, if your a networking nut, use Windows Server, then you can setup an Active Directory! Yaay.. lol