I'm in the same boat as batninth in understanding how you have it set up now.
The Netcomm modem router has one USB and one ethernet port. If it will accept two devices - one on USB, one on ethernet - then I'd connect both the desktop and the lappy via that modem router (one to the USB, one to the ethernet), and not use the Netgear. Sell the Netgear on eBay.
It the Netcomm will only allow one connection, then I'd connect both devices to the Netgear, and the Netgear to the ethernet port on the Netcomm.
You don't mention the Netgear model, but if it's a modem/router, or a wireless modem router, I'd use it on its own and sell the Netcomm on eBay.
Little boxes, or the model number of the Netgear, would help.
With a laptop, I think wireless internet is essential. The Netgear DG834G is available at reasonable prices, and with that and a wireless PCMCIA card (if your laptop doesn't have built-in wifi), you can roam round the house...