Can't slide to unlock iPhone

Question

Does anyone experience this kind of problem?
And how do you fix it?
It's exacly like this video.
http://www.youtube.com/watch?v=WCQi52Bv2dk
Can't unlock my iphone by slide the bar and in the mean time
the monitor's like dead, can't play ipod either.
And I found out that if I knock it really hard, it will back to normal.
But could happen again right next time I try to unlock it.
Or if I sync with iTunes, it will back to normal.
And this could keep it normal for days, then happen again.
I thought it has something to do with the software.
But after I upgradedto OS3.0 and "did not" resotre it,it still happened.
I think it's a hardware problem.
Should I just send it back to repair?

Answer 1

I had this problem intermittently a few months ago on my iPhone 2G. I used to clean the screen and it would let me "slide to unlock" as usual.
Two days ago, the slide bar was stuck again. Cleaning the screen did not work, so I forced it to shut down by pressing the front and top buttons. This did not rectify the issue. I then tried connecting to iTunes and syncing/backing up just to see if something would jolt it awake--nothing. I ended up forcing it to shut down again and it finally worked when I rebooted it.
It worked for a day, then stopped again. I tried the above steps and those didn't work, so I restored the factory settings then restored from my backup. This did not work, so I took it to an Apple Genius Bar. The Genius told me that the touch screen was dead and it would mean either I spend $100+ on a repair or get a new phone. Unfortunately, they were renovating the store, so they couldn't assist me with either fix, anyway ("You'll have to call the help line or take it to the nearest Apple store 95 miles away"). Since my phone is no longer under warranty (I've had it about two years), these options would be out of my pocket and there was nothing Apple would do about the cost. I understand the warranty issue, but I invested $400 on a product that was essentially useless after two years due to component faultiness and not user abuse! If I spend another $200 on a new one, should I expect to have to go through this again in a couple years? It is very disappointing, to say the least.