Can't Format Macbook Pro 7.1 PLEASE HELP

[Bizo]

dear all , i accidentaly formated the mac book pro 7.1 , i mean i erased all the hdd , and installed win7 ! , now i got mac osx 10.5 , and Snow leopard , they are both failing to boot , the apple logo comes up after holding the "C" button at the beginning and after a while , a message appears that tell's me to " you must restart your system , press / hold the power button" , after doing so , same and same , no progress ! can anyone please HELP , this really is urgent !!! thanks in advance

 

[djackmac]

Sounds like bad RAM, bad superdrive, bad logic board, or it doesn't like either one of the installers you are using. Are both the disks black retail disks or gray OEM disks from say...another machine?