There have been a few theories around claiming Henry Allen is Zoom. The Zoom 'eye' matching theory might have provided some substance but does not comply with the show's story line.
So let's cut right to the chase.
If you remember a scene in the finale of Season 1 they show Henry Allen in his prison cell looking out at the singularity worrying for Barry.
In the 2nd episode of Season 2, Jay Garrick narrates a Flashback of his fight with Zoom on Earth-2 right before the singularity opened. So unless Zoom can run at speeds that can even cut through dimensions and create a speed mirage that doesn't look like him in any way, making him Omnipresent in 2 earths he isn't Henry Allen.
And also Jay says he has been fighting Zoom for 2 years before that event^ . Barry wasn't even the Flash that long ago. Therefore it is impossible for Zoom to know that he had to take Barry out to become the only Speedster Alive.