As far as I understand from your description, the guy's "story" makes sense, despite the fact it may not be the ONLY solution. The "wireless laptop" has a wireless receiver ONLY (built in). You will always be able connect your laptop to your existing network, with an ethernet cable (RJ-45). However, if you want to connect wirelessly to a network, you have to have an emitter (access point) somewhere. Normally this would be done with a wireless router (which is a router plus an access point built in the router). That's why he is suggesting you to change your present router for a new one. Many models of wireless routers have several RJ45 ports, so you would always be able to use it in the way you use you present router as well (plus the Access Point possibility).

There is another slightly less expensive suggestion: keep you present router and connect to it, in addition, an external Access Point emitter (many of these external devices can work in several modes - emitter, receiver, repeater). I hope my explanation was clear!

-- José.