Your router has wireless capabilities, yes?
Make and model of router?
What operating system on the laptop? Way to get to 'network connections' varies from OS to OS; however, on pretty much any version of Windows, you can connect to a new wireless network by opening Control Panel, and going to Network Connections. One other way is by clicking "Connect To" in your Start menu (you'll need to add that, as it's not there by default.)
Of course, you'll need to know the SSID (wireless name) and password for your wireless (you've locked it down, yes?) in order to connect.
Windows will, by default, remember all wireless networks that you connect to, unless you specifically tell it to not
remember the network (the option is given when you create the connection.) So, that's something to not have to worry about.