2gig of ram is the bare minimum to run the game with windows 7.
Except for increasing your amount of ram there is not much you can do.
I dual boot with XP Pro 32 bit, and it runs the same there as it does on here (7 Ult). Like I also mentioned, I've also tried running it on "low" settings, and I've even lowered it past the default "low" settings as well, and it still lags and stutters like crazy. I really like this game a lot, but I haven't had any other game I've played run this badly before.
