MacBook Pro 15" 2007 won't turn on after leaving Snow Leopard update in the drive

Question

Hi Everyone,
After installing Snow Leopard 10.6.3, I left the cd in the drive when I turned the computer off. When I tried to turn the computer back on again, the screen told me that I needed to restart the computer by holding down on the power button. So I did, but the message came up again. I did it again. The third time, the computer wouldn't turn on at all.
I removed the cd by opening up my computer--something I had done in the past because of problems with the keyboard. (The keyboard was never fixed, and the trackpad didn't work either, so I used USB connections.The powerbutton never was affected though)
Two questions:
First, what would you say is the culprit in the first problem with the messages to restart the computer? How might I address this?
Second, knowing the secondary information about the keyboard connections, how might this affect fixing the problem? Could the powerbutton now be affected, especially since I lifted the keyboard off?
Lastly, I've looked into restarting the SMC, and turning on the computer without the button. I have tried the first of these two options, and will soon attempt the second (If anyone can send me a link to better explain turning on the computer without a button for my model, I'd be grateful.)
Any more advice (short of bringing it into the shop!) would be helpful.

Answer 1

Try powering up and push in your install disc(use your original install disk if you have it, maybe try the retail SL disc white with the cat as a second choice) holding the C key (this should make it boot from the disc) select your language, click continue, in the next screen in the menu bar click Utilities/Disk utilities, select (highlight your volume from the left column, default name is Macintosh HD, unless you renamed it) click the first aid tab, then click verify disk, if it comes up with errors (they will be in red font) if you get errors, run repair disk, run it repeatedly if necessary till it comes up with this disk seems ok (in green font)
Then run permissions repair.
Log out and reboot see what you get.
You may have to reinstall the 10.6.3 OSX again, do this by powering up and pushing in the disk holding the C key and follow the prompts. if you have a successful install, eject the disc, and reboot. The next thing you need to do is run software update, there will be many and you want to do them one at a time. (use an ethernet connection as opposed to wireless, as there is much chance of corruptions. The first one to run is the 10.6.8 combined v 1.1, the keep running software update one at a time till there are none offered.
Hope this helps