I should mention that network switches don't have any ability to assign IP addresses. In other words, they can't act as DHCP servers - therefore there's nothing to disable!
If your network has a router (or a modem-router), configurations should be made in it...
BTW, you can disable DHCP in Windows (i.e. assigning a fixed IP address to each computer on the network) but following this
(the part that should interest you has the title "If Your Router Doesn't Let You Set Static Local IPs").
In case of a problem or clarification, don't hesitate to post me a reply before rejecting my answer.If you are satisfied, rate my solution with the "thumbs" or (even better) add a testimonial.