As you don't know about Mac filtering it is safe to assume you haven't got it, likewise with the b and g.
Resetting your router will not affect the ethernet connections and I strongly recommend that as the next step.
With no security settings at all everything should hopefully connect.
Pointless using a USB wifi dongle, which are precarious at best, when you have internal wifi.
Reset, switch everything off as before and tell me exactly what happens. Do you get the wifi icon in your system tray on the laptop? It looks lke a monitor with )) to the right side.