1999 Nissan Sentra Haywire

Ok, so the car died. Meaning it wouldnt start. So my hubby suggested that it be the starter. Got it changed. It started fine and drove w/o probs for about 2 hours then I was stranded. Connected cables and boom, I was up and running again. Got home and it died again. So the hubby took the battery to get checked. AZ said it was good. He reinstalled it backward and the horn went off along with the lights flashing. I suggested he turn it around ;-) well, the car starts but now the wipers, ac, interior light, cdplayer and radio, windows, will not operate. He replaced all the fuses, the horn fuse was the only one split. And still no action. Before all this, the cd player would not eject the cd-ever, the interior lights stopped working when the headlights were turned on, and the interior light seemed to be corroding even tho I replaced it 2x!
the engine is a beaut, it flows without a problem. What is going on!