You just need to blur the top layer, and you're done. Select the Blurry layer and then choose Filter, Blur, Gaussian Blur. Use enough of the effect to blur the scene, but not so much that it renders the entire photo and all of its details completely indistinguishable. I can't suggest a specific value, because Gaussian Blur's impact varies depending on the resolution of the photo. As a rule of thumb, though, you might want to start around 14 and see if you like the effect.
Now, with this layer still selected, right-click it in the Layers Palette and change the mode from Normal to Multiply. You should immediately see the effect. The final step is to dial in just the amount of Orton Effect that you want by using the Opacity slider in the Layers Palette to adjust the brightness and blur.