It sounds like you have corrupted the master boot file on your hard drive. Judging by the age of your computer you may need to do a "Target" boot up onto another computer perhaps your parent's. You can find information for doing that.
Explaining the Mac OS X Lion Clean Install
If you are successful open up Disk Utility on the useable Mac and have it look for your computer's HD. If it still shows it grayed out that means it can't recognize the boot up block most likely. If clicking on that doesn't do anything then click on first aid and try to repair it. If that fails try again to partition it. If you get that far change it to 2 partitions you don't really have to name it at this point.
This "OVER" writes the master boot block on your hd. You should then be able to move forward. If any of this helps and you can now see your hd then open your browser on your parents computer and try to download Lion again to your parents computer while still in Target mode with yours. When the download completes click on it and start up the program. When it opens you will be asked which drive you want to install Lion on. Select your computer's hd and then follow the instructions.
Average install is around 45 min if I recall. If none of this works you may have to either take it to a tech who can overcome it. I could if I had it here but thats not possible. A true tech can fix that. Also, you may want to just buy a new hard drive and update your Mac.
Install OS X Lion Using a Bootable DVD
There are many websites that will show you how to do that if you google it. May 'the force' be with you! Good luck. Apr 12, 3: Apr 12, 5: Given the age of your equipment, if you have firewire then yes, you will need a cable.
Also, just FYI, if you have an external drive you can hook up to your parents computer you can install Lion on it just by selecting it when you go to install. When done you can hook it up to your mac by USB. After your mac does its self check it will reveal your 'start up' drive options. You should then see your external drive. Click on it and your mac will now run off that new drive, just not quite as quick as it usually runs. Once you are up on that drive open DU again and try to repair-partition-restore your original drive before you give up. After you have managed to recover your original HD when you go to boot up on it you should reset the pram by holding down the shift-option-command-r keys all at the same time.
You can manage this with your right hand if you try; then hit the start button with your left. As soon as you hear a second chime release all four keys and let it boot up. This is a lot of info and Im not going to be online for awhile. Just take your time and go through it slowly. Personally I like the external drive option, but if you don't have one that can be spendy too.
The four keys are the Option, Command, P, and R keys. Everything else is good. As soon as your Mac restarts, hold down the "C" key. This will force your Mac to boot from the DVD. The boot process will take a long time, so be patient.
Be sure to turn on all monitors that are connected to your Mac because in some multi-monitor setups, the main display may not be the default monitor used by the OS X Lion installer. Disk Utility will open and display a list of connected drives. This process can take some time, so be patient. Select the disk you wish to be the target for your OS X Lion install.
Remember that we're going to erase this disk, so if you haven't performed a current backup of the data on the disk, stop and do it now. If you have a current backup, then you're ready to proceed. Select the disk you wish to erase. A drop-down sheet will appear, asking you to confirm that you wish to erase the target disk. Click Erase. Disk Utility will erase the drive.
A list of disks will appear; select the disk you wish to install OS X Lion on. This should be the same disk you erased earlier. Click the Install button.
The Lion installer will copy the necessary files to the target disk. The installer may also download necessary components from the Apple web site. In our installation tests, there were never any downloads, but this feature may ensure that the installation has the latest updates, and there may not have been any current updates. A progress bar will display, with an estimate of the time to copy the needed files. Once all the necessary files are copied to the target disk, your Mac will restart. After your Mac restarts, the installation process will continue.
A progress bar will display, with an estimate of the installation time, which can run from 10 to 30 minutes. Once you see the installation progress bar, the install process is identical to steps outlined in the following article:. Finish the installation by following from page 4 of the article: Share Pin Email. Tom Nelson has written hundreds of articles, tutorials, and reviews for Other World Computing and About.