As you may already have figured out you can access your phone using the MyMobiler utility when syncing to your PC.
There's a reg key adjustment for screen sensitivity which I'd check if I was you. Of course if it's a hardware issue perhaps you've got insurance. I'd search for the registry adjustment and go for the hard reset only as a last resort to confirm whether it's hardware or not.
Let me know if you're not finding the reg key. Good luck.
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