2.1 renders phone unusable

Question

As of yesterday, phone updated to 2.1 Used the phone once in the evening, after this, the phone is stuck in the "phone" section of the applications. Pressing the main button won't take me back to the menu but the button is clearly working as double tapping takes me to the favorites. I could however move between Favourites, Recent, Contacts, Dial etc and even make a phone call.
So this morning I thought I'd take a properly look, only to find, I can't enter my passcode on the screen. Got four dots in the code window but thats it. Tried again later, buttons light up blue as I press them, but no dots in the window...
What do I do with it now????

Answer 1

the best way to fix this is to do a restore;
first put the phone in DFU mode by holding down both the home button and sleep/wake button while the phone is connected to your computer make sure the phone is turned off hold both buttons down for 10 secs then let go off the sleep wake button and only hold onto the home button (Note: when you do this you will not be able to use your phone until the phone has been restored)
iTunes will then tell you that it has found a phone in recovery mode click ok
Then click on the restore button it will download a fresh version of 2.1 when this is done your phone will re activate
if you want the best chance of having the phone work like new do not restore from a back up it might make a difference however if you can not live with out previous app saves or sms messages you may not want to do this