A while ago I replaced the glass on my wife's iPhone 3GS, and it worked great (Thanks ifixit). Since then, the phone has taken another hit; the glass is cracked but not badly, but it doesn't respond to touch.

I did a power button + home button reboot, then checked connections 2, 3, and the other ribbon connection. Everything there seems ok.

So what next? Is there any good in doing a firmware reset? Should I just replace the glass again, or buy the whole display assembly? Is the phone itself a paperweight (dead board or connections), or needing to go back to Apple?

I want to make sure I'm doing stuff in the proper order and buying the right parts, Thanks for any advice up front.