Did you get all your 3 2k7 copies from the same store?
My first copy of 2k7 which I got it in a Best Buy pretty far from my house since it was the only Best Buy that had the game on opening. This game that I got from that Best Buy was giving me the "disk error" thing almost every other day. After a couple of days having to deal with this "drity" crap. I took it back to the nearest Best Buy(not the 1st store) and got a new copy. This is the copy I currently have, though it still gives me the saem "dirty disk error" crap, atleast iot doesnt do it every other game.
Maybe getting the game from another store that's not nearby will help.
In other notes... I neve rhad a problem with GOW, but I did have some freezgin on Saints Row
ELITE SIMS admin
http://online.2ksports.com/league/index?p=360&t=NBA2K8&l=222473