How to update my PSP Pandora battery firmware?

Ok, I'm running (from my window of memory stick on my PSP) M33-6 next to it says PSP updaye ver. 5.00, also I have 5.50 GEN-D2and have 1.50 kernel addon for 4.01. I'm wanting to update to 5.50 GEN D-3. So , I went to the PandoraSales.com and downloaded the update for the 5.50 GEN-D3 to my desktop. After this I'm totally lost as to what to do. I want to play some God of War: Ghost of Sparta and have been reading that I'm in need of an update? Help..I'm sooo stuck. Thanks for any and all help.
**WhenI download the 5.50 GEN-D3 Installer , am I supposed to download it to my desktop? or to ....????***
HoustonTX224

Stay with 5.00m33-6 I say, it's the best PSP CFW around. You shouldn't have problems running any ISO/CSOs.http://forum.romulation.net/index.php?topic=53840.0It'll work fine for you on m33-6.

No luck...I downloaded the God of War : Ghost of Sparta form that link...screen just stayed black...Noooooo..lol