belkin wireless G MIMO help!?!?!?

Log back into your router and turn NAT back on. NAT stands for network address translation and allows you to share your assigned internet IP (your external IP - the one which the rest of the world sees you as) among several computers by creating pseudo-IP's (internal IP address, typically 192.168.0.x) for each computer on your internal network.

If you can't get back on the router control panel by typing the normal IP address in the computer browser address bar, there is usually a button on the back of the router to reset it to factory defaults. Just hold it in with a pen until the lights start going crazy. You can then log on to the router with the factory default IP. You may have to look it up for your particular router model, but is is typically 192.168.1.1 or 192.168.0.1, in rare cases it can be 192.168.2.1. The manuals can typically be found at the vendor site, just follow the initial instructions for getting on the router control panel.

Of course you will need to set up your router again, including DHCP server (which is what assigns the pseudo-IP's to each of your computers so make sure this is ON), wireless security (WPA2-AES cipher recommended if all of your wireless equipment is newer and supports it), and MAC filter if you use it. Every ethernet adapter has a unique MAC address.

A MAC filter allows only network adapters which you specify to use your network. These addresses are typically on the labels of your device, or you can type IPconfig /all in a DOS box (type window-key r together and type cmd and then enter to get a DOS box) in Windows to see it on a computer. Note if your computer has wired and wireless ethernet there will be a MAC address for each one. It just adds another layer of security, but can be spoofed by an experienced hacker. That is why having good wireless security is a must.

I strongly suggest you leave the router firewall on and properly set up the ports you may need to open up for your xbox. Most routers use dynamic port configuration nowadays so you usually don't have to do anything. If you must, put your xbox IP (or better yet the xbox network adapter MAC address if your router allows for it - this will ensure that an unintended computer doesn't end up in the DMZ if DHCP reassigns IP addresses) out into the DMZ (demilitarized zone). This will put your xbox outside the firewall, but leave everything else on your network protected by the router firewall.

As far as your xbox lagging. Note what ethernt port your xbox (theres usually 4-5 and they are numbered) is plugged into. If you are lucky there may be a tab called QoS standing for Quality of Service in your router control panel someplace. Put the highest priority possible on your xbox ethernet port. That should help lower the latency created by your router. This basically tells the router that this ports traffic is the most important. Take care of any traffic to or from it before doing anything else.

Chances are there is disturbance from items around the home. Anything from microwaves to mobile phones can cause a disturbance because of the set frequency. Another possibility is a lose connection causing disconnections. You can change router settings through internet explorer, you can get the internet link from under the router or in the manual e.g. 192.168.0.1 and you require a user name and password depending on your router company. It might be that you might just need to change the "channel" set for the router. The alternative would have to be that you change from a wireless connection to a wired connection through the ethernet port in your computer.