[haus]

Bumping a thread after 35 minutes...you need to be more patient.

Also you weren't very clear in your post - you didn't mention what software you are running, what ROM you are running, who your carrier is, whether your phone was new or bought used (Ebay, Craigslist, etc.), whether you've tried a soft reset, a hard reset, etc.

But based on your symptoms - screen works most of the time, not while a call is coming in - I'd venture a guess that you have some software like Pocket Shield on there that (optionally) locks the screen while a call is coming in / in progress.

Edit 2: It's not pocket shield per se. That app shows a clear "locked" screen during a call. But there are other utilities that may offer similar functionality without being so obvious that they have locked the screen.