It should work, but it may be a challenge getting it configured properly. You'll have to struggle with multiple IP subnets as the ICS system shares the connection with the router, which will then distribute the connection a second time through a different subnet. Furthermore, with ICS that computer must be on whenever another system wishes to access the internet.
If you can, push your ISP to give you a different modem, one with an RJ45 ethernet connection. That will have two advantages. First, this sharing problem will go away. Second, your connection will be more stable as you won't be relying on a USB connection. The idea of USB networking was cobbled together by the DSL modem industry as a means of connecting to older computers that had only USB ports and no ethernet ports. They thought they would save the consumers from having to open their computers and install a network card. Instead, they saddled the consumers with an unstable connection through a device that was not designed to do that. Most newer computers have ethernet ports now, and the USB-only modems are drifting into obsolence.
I'm in the process of planning to set up a home network. I have 2 desktop PCs and a laptop. I bought a wireless router/switch
(http://www.netgear.com/products/details/MR814.php) on ebay and I'll be getting a free ADSL modem
(http://www.dlink.com.au/products/broadband/dsl200/) when I sign up with my ISP.
The modem has only a USB interface, not an RJ-45, so I figured what I would do is hook it up to one of the PCs, then use that PC's network card to connect to the router and share the internet connection that way using MS Windows's Internet Connection sharing utility. I talked to some friends with a bit more networking experience who said that it wouldn't work that way, that I would be better off getting an ADSL modem with an RJ-45 interface and plugging it directly into the router/switch. Is it possible to do it the way I've been planning (hook the USB modem into one PC and connect the PC's network card to the router, in order to share the internet connection) or am I better off looking for a new modem?