My car won't start. Please help?

[DREW D]

I tried starting my car about 30 minutes ago, and when I turned the key, nothing happened. The engine did not even budge. Then I tried the lights, and they were not working too, so I thought the battery was very low. Then, I tried hitting the lock/unlock button, and nothing happened. I also tried moving the mirrors, and you guessed it, it didnt work. Then I tried pulling the lever to pop the hood, and that didn't work. I thought that was weird because i didnt think it ran on electricity. I forced the hood open and looked at the battery, which had whatever the white stuff is that gathers around the wing nuts on the battery. I scraped that off, and tried a jumper, which had a low battery so that didn't work. I am charging the jumper now, but yesterday, my car was fine. I drove around with it, and made sure no lights were on when I turned the car off. Please tell me either what is the problem with my car, or what I can do to fix it without bringing it to a shop, or both. Thanks