First time I installed it, I would get in game to the first menu but it would have no text. The menu would still "work" but I was selecting blank rectangles. I saw no specific fix for this in any of the forums/sites/newsgroups that google searched for me so I just uninstalled and re-installed. Now it runs fine, Everything maxxed out at my native resolution of 1280x1024 with 4xAA.
If all else fails try re-installing this game, and roll up a doobie to pass the 40 minutes of time it will take to install again. Cool game but the textures are still pretty simple in spots and the desaturated look is borderline black and white. I'm thinking that has a lot to do with its performance superiority over titles like Crysis.
update: I can now play at 2560x1024 resolution and it runs pretty well (>30fps). The significance of that is that GOW supports dual monitors with my 8800GT. This will do until I get my 24in LCD and not need to worry about the half inch border in the middle. But until then, it's pretty engrossing to play at such a sick resolution and the game offered other widescreen resolutions and scaled the picture accordingly if i picked any that were lower than the native res.