BleepingComputer.com: PCs hooked up to switch losing internet but router PC is ok?

My household has exhausted all of our resources trying to figure out what is wrong with our home set up.

Our ISP is Comcast cable. We have a Motorola modem which is plugged into a Wireless G Netgear router. There is a computer hardwired to the router. We have another wire plugged into the router that runs through our ceiling to the other side of the house where it is connected to a Netgear switch. Plugged into the switch is two PCs and an Xbox 360. We also have one laptop and a Nintendo Wii that are wireless.

We keep losing internet to the 2 PCs and the Xbox 360 that are attached to the switch. We have gone months with it working fine but every few weeks or so we have a huge problem with the internet just going down and it is getting very tiresome.

We've tried applying static IP addresses and resetting our network hardware to factory default but we're still having problems.

Does anyone have any ideas on how we can fix this? Anything suggestions would be greatly appreciated. Thank you so much.