Hallelujah!
At first I thought this game was repetitive but as I got into it I couldn't stop playing! For the added replay value there should be a bonus score system for killing zombies and finishing levels in a certain time. If you're ever gonna make another Father O'Malley game please let it be a prequel with an epic boss fight with the Zombie Lord. And don't go ruining it with upgrades, the cross throwing is good enough :D
And that would propably make this the first game series ever to have only prequels, not sequels (if you made first part 2 and the part 1). If you're willing to do more than one of these, try making the other one Pitfall-ish (this game really reminded me of the old Pitfall Harry series :D)