Macbook Pro A1278 will not boot from cd, nor other boot commands

I bought this Macbook Pro A1278 used last November and it worked great. About 2 weeks ago the hard drive was making a clicking noise but still worked fine. 2 days later when I booted up the MBP it would only boot to the folder with question mark. I took the hard drive out to find that it was dead. I purchased a new 500GB hard drive, installed it and can't get it to boot from the 10.6.4 disc that I received with the macbook. I also tried resetting PRAM and nothing! I also tried booting holdind down the option key and it boots to a grey screen with a lock. I contacted the seller I purchased from and of course 11 months later they said they know nothing about another password. Can someone PLEASE HELP, I paid over $1000 for this laptop about 11 months ago.

The machine is protected by a firmware password which is different from the normal administrative password.

Read this info from Apple regarding a firmware password.

Firmware passwords are usually setup to prevent someone from tampering with or changing out the hard drive in the event the machine is stolen. I don't want to alarm you but are you sure the person whom you purchased this machine from was the legal owner?

Yes, purchased off ebay last may and the seller is still currently selling on ebay. Everything was fine for 11 months until hard drive went bad. This was my first mac and so im still fairly new to Apple products. I figured he must at some point knew the password since it was a fresh install when i got it.

If you're certain the machine wasn't stolen.... although I find it strange that he set a firmware password on the machine and then forgets it?

Have you been in touch with the seller and let him know about the firmware password and now you have a machine that's useless?

Anyway, check out this LINK and try the method that's recommended to get around the firmware password. Let us know if this works for you.