If the ONLY possible thing it could be are the steps that took place in that video, then you shouldn't do a system restore if you've undone them. When you're getting this lag, (assuming it's network lag) bring down the console and type 'netgraph 1'. If the white graph at the bottom of the screen stays low, then your packets are getting through. But, if there are a lot of spikes or large blocks, you're dropping packets. Could we get some information on your network/internet setup?