Can you see the wireless signal in the room where you want to place the bridge? The SMC gateway has many complaints about its wireless range and performance. If I were you, I would get my own router (match manufacturer with the chosen bridge), have Comcast place the SMC gateway into bridge mode to disable its router function, and then connect/configure the new router. Then connect/configure the bridge.
If you want to try with the SMC, verify a proper wireless signal in the desired location using a current wireless device that IS working. Then tell us the exact make/model of bridge and exactly how you have the gateway configured, both local IP setup and wireless setup.
At first blush that looks normal, but the DHCP Server: OFF under LAN Port on the bridge concerns me. Did you connect a device to the bridge to get this info, or did you use a computer on the gateway pointed at http://10.0.0.9? What does the DHCP Connection button on the Device Status page say? Also, what does the IP Address Setup page say?
Clearly the bridge is addressable and talking to the gateway. It has an IP address that will route on the same subnet as the gateway. The question is if that IP address is static or DHCP derived. If statically assigned, it may conflict, which is why I'm asking for the above information.
The gateway lists 4 wireless clients, one of which I assume is the bridge, along with one wired client. What are their IP addresses and what are they (type of device, etc)?
When you connect the TV or receiver to the ethernet port on the bridge, what does it show for network status? What about network setup settings? If either has a proxy setting, disable it or turn it off. Use DHCP (Or automatic IP assignment), but if that fails (some embedded DHCP clients are flaky) then manually assign an IP like 10.0.0.250, subnet 255.255.255.0, DNS matching the DNS settings on the gateway or bridge, default gateway of 10.0.0.1. On the other device use 10.0.0.251 instead of 10.0.0.250 (since it's already used), but the other settings are same. Does that work any better?
If you want to connect both devices at the same time, get an ethernet switch and connect that to the ethernet port on the bridge. Or get a bridge with a number of ethernet ports instead of just one.
OK, that looks good. I don't know why it says DHCP Server: OFF when its clearly setup to use DHCP to get it's IP address and appears to be working normally. When you connect your laptop to the bridge, can it access the Internet? Is that what you are using to post these messages? If so, make sure your wireless adapter is disabled (to ensure using the bridge connection) and try going to any site, like http://www.google.com. Did it work? If so, the bridge is working normally and doing its job, so we have to assume the other devices you are connecting to it are not configured properly. If you can't get to Google using only the ethernet connection, then post the output of ipconfig /all and route print from the laptop while connected to the bridge with only ethernet connected, wireless disabled.