sorry for my bad english i am french :/
i try open ticket on bugtracker (but they are close ) here :

Backtrack 5 - Bug #102: Backtrack 5 : not boot - Redmine

i have download BT5 64 bits with gnome

I have laptop "ACER ASPIRE 5732Z" with "Mobile Intel(R) 4 Series Express Chipset Family" video cart
When i boot i select first option by default for launche after there are a red square with black background and with font
after that my screen is black, cd-rom running few seconds and stop

thank you,