I dont have my owners manual in front of me, so I cant tell you which fuse, but your fusebox is under the drivers side footwell area. Get down there, look up, towards the side closest to your door, and its a slim black box. One end has a little tab you push or pull and the cover will come off.
Sounds like you might have just popped the fuse. I know when I last disconnected my battery, the way it popped when I reconnected, sure sounded like I might have blown something, but all was well...knock on wood.
*Edit, funny thing is I have an aftermarket Pioneer double din head unit which saves all my settings. (EQ settings, radio presets, etc, everything but the clock) I had it disconnected for nearly a week or two when I traded my Edge in and picked the Explorer up. I hooked it up and all my settings were there still.
I unhooked my battery yesterday for a brief period while I was wiring up my new headlights, and when I was done, everything was reset like the unit was brand new for some reason.