My iPhone 3GS is just showing a blank white screen how do I unfreeze it?

I tried holding the hold button to turn it off but that's not working. Its been like this for about three hours and hasn't changed. How can I unfreeze it?

Hold it and turn it off. Then turn it back on. Or you could just wait for it to unfreeze if your talking about the Internet page.

You should hold both the power button and the home button down at the same time, and then count to seven or until the phone reboots, then let go. This hard resets your phone, and works everytime! (If it doesn't, plug it in, then try again.)