if u buy a wireless router..... you can plug a network cable from modem in the WAN port on the back of the wireless router
the wireless router should automaticly then be assigned an ip address range.
you then need to log on to the wireless router and set the wireless properties eg.. wpa password... otherwise the whole street will be enjoying your free high speed internet
if you setup your internet on your modem you shouldnt have too many dramas with setting up the router.
finally both your laptop and iphone and ipad and anything else wireless in your house should have no problems connecting