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On my computer, Windows can begin startup (giving me a the option to press F8 to select safe mode) before blue screening and restarting. If I boot from an external Ultimate Boot CD, I can't read the drive at all.
If the drive is unreadable, how can Windows even attempt to start up?
We have a faq. When you're new to a site, it's generally polite to read stuff like that. The big blue banner at the top of the page suggesting that you read it when you sign us isn't for decoration.
Booting is a complex, multi-step process, the initial steps of which require only a valid MBR/GPT and a readable bootloader. The initial two steps do not require the system partition to be intact or mountable.
The Windows Boot Manager (a.k.a. NTLDR or BOOTMGR) step includes the prompt that you mentioned, asking the user to press F8 for advanced startup options. Only at this point in the boot process does Boot Manager even load the drivers that are required to mount an NTFS partition.
Of course, the subsequent step of actually mounting the system partition will fail if the partition is completely unreadable, as appears to be the case in your situation.
Your hard drive might be totally messed up, the the particular sectors needed to intially boot might be in tact.
Same thing would go for booting from the CD, if the Hard drive is over toast, it's likely that the boot CD might not be much help. However, i think what may be more likely is your boot cd doesn't have the driver needed to load your storage controller, which is what your hard drive is connected to. if it can't load the storage controller, it won't see your hard drive. if the computer happens to be a laptop, try booting into the bios and change the storage adapter to compatability mode and then booting to the CD.
