|In a Two system network a Switch cannot be used to share internet.|
What kind of broadband modem do you have? Does it have both a USB and RJ45 ethernet port? If so you would use the USB to connect to one of your systems (Host) and then connect the two computers using a crossover ethernet cable. Then you enable internet connection sharing (ICS) in the host PC and configure the client to connect via the host. Windows help has a walkthrough that gives details of how to configure this. If the modem has only ethernet then you would need to have two network cards in one of your systems. Does either the laptop or desktop have two or more RJ45 ethernet ports?
Downside to this setup is that the client system can only get internet when the host is running.
A better solution would be to ditch the switch and get a SOHO router. Most come with inbuilt 4 port switch. You then connect from Modem to Router WAN port and each PC connects to a router LAN port. Each system then can get internet independently.
Whatever way you go the switch you have is useless for sharing internet in your case.
Goin' Fishin' (Some day)