You should install 4.1 on your 3G and I think it will fix it. I too experienced the "freezes from hell" with iOS 4.0 running on my 3G, but ever since upgrading

You should install 4.1 on your 3G and I think it will fix it. I too experienced the "freezes from hell" with iOS 4.0 running on my 3G, but ever since upgrading to 4.1 on Wednesday I've had no more freezes.