W500.windows 7.Crashed! and since then cannot start windows!

[K-a-M-u-Z-u]

Hi.
i got a thinkpad w500 laptop and windows 7 build 7600. for 8 months everything went fine.
a week ago, i got BSOD during video encoding for my ipod.i tought it was a random glitch.
since then, the computer randomly crashes.more and more often.
until two days ago.
windows just wont start, and i get BSOD with MEMORY_MANAGEMENT message.
each time windows suggest startup repair, it wont help.
i tought the MEMORY_MANAGEMENT error could regard to damage to the memory modules, so i tried to run some memory testing tools with no results.i tried to run the computer with just one module at a time(got two CL7 2GB 1066MHZ) to see if i can find a faulty one, but both of them gave the same result.

tried to use system restore.it worked one time, but few minutes after windows start i got the BSOD.
i have tried starting in safe mode and it didn't worked.

i tried to re-install windows 7, (upgrade and clean install+format):
1.UPGRADE:it says i need to do it from withing windows.
2.CLEAN:it start expending files, and then i get the error message:

Windows installation encountered an unexpected error.verify installation sources are accessible, and restart the installation"
ERROR CODE: 0xC0000005

i even tried to install vista SP1 and it just hold in EXPENDING FILES.

*i have run UBUNTU LIVE CD and the computer start with it just fine, and i even get access to all the windows files.(before i formatted).but i cant install ubuntu and get a message during installation regarding accessing the source just like in windows 7 installation.

**i have tried a backup windows 7 disc , so its not the installation disc.
***i have tried using external dvd drive with the ultrabay drive disconected, and the get the same 0xC0000005 error code.

what could be the problem?

*could it be related to the TPM (Security chip) and if so, i could i just reset the computer to factory defaults?

i am desperate!