Photoshop users? Help me!

OK--I've accidentally turned something on in PhotoShop and I want it to go away and can't figure it out. Here's what it looks like:

Photo here, because I can't figure out how to directly link to an image on this silly yahoo thing, and I have no FTP access here at work.

Anyone? Bueller? Bueller?

I'm editing a bunch of nav buttons this morning, and whatever that is is sitting on top of all my images and making them hard to work with.

Help me!