You can follow these steps to setting up an ad-hoc connection on your computer.
Go to Start > then right-click on Network and select Properties (on Windows Vista/7, go to your Network and Sharing Center under Start > Control Panel > Network and Internet).
Click on the "Set up a connection or network" option.
Select "Set up a wireless ad-hoc network" (Vista/7 have this as "Set up a new network"). Click Next.
Choose a name for your ad hoc network, enable encryption, and check the box to save the network. Your wireless network will then be created and your wireless adapter will start broadcasting.
Go to Network Connections in your Control Panel by going to Start > Control Panel > Network and Internet Connections > Network Connections.
Right-click your Internet connection that you want to share (e.g., Local Area Connection) and click Properties.
Click the Advanced tab.Under Internet Connection Sharing, check "Allow other network users to connect through this computer's Internet connection"
Click OK and you will receive a message about your LAN adapter being set to 192.168.0.1.
Click Yes to confirm you want to enable Internet Connection Sharing.
Your Internet connection will now be shared to other computers on your local network; if you connect them via wire (either directly or through a wireless hub), you're all set.
CONVERSELY:
You can just set up your adsl2+ router and stick an ethernet cable running from one of the LAN ports to your computer and use that connection as wired while having a wireless connection NOT emanating from your laptop.
I would select the second method of using the router.
Hope this helps.