I think it is better than every component of a wireless network be of the same brand to minimize incompatibilities.
The components are cable modem, wireless router to connect to the cable modem, wireless card in your laptop, if it does not have it already built-in.
I prefer Linksys brand name myself but it is your decision.
Chose the speed of your wireless network standard:
If your laptop already has a G wireless card built-in then chose G wireless router. Otherwise B standard is good enough I think.
The connection from the cable modem to the desktop could USB or ETHERNET. Buy the wireless router with both USB and ETHERNET connections. I prefer to use the ethernet connection.
Buy the Wireless Broadband router and follow installation instructions. You will connect it to the cable model and from the wireless router to the desktop. Next you will configure the router. Linksys cd-rom does this automatically.
Buy a wireless card for your laptop if it does not have one built-in. You will need to install and configure the laptop wireless card to communicate with your router.