Connection problems with black ops 2 multi on ps3?

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Every game I join I have a solid 1 bar connection. My nat is type 2 and it says it's open. Even playing with my friends who live in a town less than half an hour from me is laggy as hell.

Ive tried port forwarding to no success. I tried giving my ps3 a static ip address and added it in the dmz settings on my router. That helped a bit but when I do that the internet doesn't work on other devices. I've tweaked every setting in my firewall options relating to wireless devices. Everything the internet says I should do doesn't work.

I started having these issues after a friend of my uncle's reboot our computer and installed windows 7 (I had vista before). Wtf is going on and how do I fix it?
When I restart my modem and router it works great for like one match then it craps out again.