said by mpovit: I think I will be getting a gateway from Comcast because wireless is included. Even if it was not a gateway and had a single port could I just plug it into the jgs524?
Nope, if you want 105 it's fine by me.
Plugging in directly wouldn't work unless you went on a business account and paid extra for "static IP's for each device.
Having/controlling the router in your home adds another security layer so I recommend it.
Of all the compromises gateways have, the wireless portion is among the worst.
Often the best placement for the modem, is a poor position for the wireless AP function and many Gateways already have weak radios and few available controls to make the best of use of what power the have.
From your description your house is fairly large and for your use your current switch is should be fine. I would rather see you spend the money on a good router and your own modem (and maybe a second AP depending on the wireless usage)