I use Elements 2.0 as well, but I am certainly no expert.

Drag the "Layer" tab down from that bit at the top right of your screen (sorry I don't know what it is called, I don't have my manual here) to allow you to click on the individual layers.

If you then click on the "Layers" menu on the Menu Bar, you will see an option called "Arrange". You can then bring individual layers forward or send them back, as necessary.

I hope that might help.