Firmware Help!

Ok, I have 3.72 firmware and I'm trying to either downgrade to 2.0 or 1.5, or get a 3.XX custom. I've heard of Pandora's battery, but I don't know what it is, nor where to find it. Please help.

What you will need to do is downgrade your PSP to 1.50 using the "Pandora's Battery and Magic Memory Stick" Method. You can either make the Battery your self but it requires a psp that already has custom firmware or 1.50 to do.
Or you can open your battery up and mess with the insides to turn it into a Pandora's Battery. Or you could just buy it off eBay.
The Magic Memory Stick is just a memory stick with certain files on them that when put together with the Pandora's Battery, it will downgrade/unbrick your PSP to 1.50.

But which PSP do you have? phat/slim?
You should definitely upgrade to custom!

check here for my starters guide.
http://pspbrew.com/forum/viewtopic.php?t=9454