belkin wifi modem/router limited connection with xbox live

[#1]

Just bought XBOX WIFI device and signed up to XBOX Live. My belkin modem/router only appears to be able to take one signal.If my laptop is connected to the internet my xbox does not connect. If my xbox is connected to xbox live  my laptop does not connect. I have also tried connecting the ethernet cable to my laptop only to find the xbox live then disconnects. Is this normal that only one device can be connected at any one time.I thought wifi routers allowed various devices to connect simultaneously. Any ideas how to resolve this clash ?

[#2]

I'm no expert but there are two things that you could check. The first is that DHCP server is switched on (it's under Lan Settings) and the second is that the connection type should be PPPoA (under internet WAN > connection type). The paths to the settings might be different depending on the model.
They're the only two that I can see that might cause problems if the wrong option is selected.
It's worth a try anyway, the router should let you connect lots of things at once so it's likely that a setting somewhere is wrong.

[#3]

I have downloaded and installed the latest firmware. I also checked router settings as you  advised and it now works OK.
Thanks ......