1997 Dodge Neon • 102,000 miles

My boyfriends car had radiator problems, it was leaking so he bought a new radiator and put it in last night. Then after when he went to start the car, it won't start. We cant figure out what's wrong. He says its turning over but none of the lights or anything in the car will work, which makes me think the battery but then wouldn't it not be turning over? I'm sorry if I'm not giving the best information, I'm not a very big car person. Any idea what it could be? Any help would be much appreciated. Hes already checked everything he took off while doing the radiator and he says everything is right.
November 13, 2012.

Check all main fuses under the hood. Check to see if you are getting spark and fuel to the engine.