Need a ARM926ejs Disassembler for Windows XP or Debian Linux

Hello,

Can anyone recommend a good program to disassemble a firmware file for a 
ARM926ejs target processor.

I've downloaded WinARM but I have not installed it yet.

I want to enhanced the functionality of a FTA receiver Viewsat MAX HD 
which has built-in support for mpeg4 video. I want to add media player 
capability (support LNA protocol) compatible with media server like 
tversity. This will eliminate the need to buy additional hardware like 
the medialoung DSM-520/510, PS3, or hacked x-box.

Can anyone also orient me as to how to dump the rom code.

I will like to first study more on the subject before I try openning the 
receiver.

Hopefully the basic OS is an embeded linux flavor and the rom can be 
dumped.

Thanks in advance.