1993 Lexus ES 300 Dead Car

Electrical problem
1993 Lexus ES 300 6 cyl Front Wheel Drive 155000 miles

Okay so my 1993 Lexus which I bought about six months ago stopped keeping a charge in the battery. Figured it was a dead battery, it sat in the driveway for about 6 - 8 weeks as I had no need to drive it. Took the battery into the store, bought a new one. Put it into the car only to find out as I was trying to attach the negative terminal that the battery was reversed in sides from the original. To make sure the car would start I took out the battery and hooked it upvia jumper cables to my car. Turned the key and nothing happened no light no sounds. Thinking that maybe the issue was that I misinterpreted something, I reversed the cables and then still have nothing. After taking the jumpers off I found that the battery produced no spark at touching the cables together, none. So now I don't know is it the battery, is it the electrical system, what? I am so baffled, never had this problem before, even with a 1992 Metro that sat in my mom's driveway for over a year started right up after a new battery was put into it. Any ideas?