Late 2004 ibook HD replaced, still not functioning

Hello. I have a late 2004 (I believe) ibook G4 - 1064MHZ, 256MB RAM, 30GB HD. Sometime in 2006/2007 the ibook stopped working, it was a slow death which I associated with the hard drive. When the ibook was on and I attempted to move files around the ibook would turn off, as far as I can remember. Furthermore, after that, the ibook stopped booting alltogether. When I would press the power button, I'd hear the Macintosh chime then I would hear some very raunchy sounds, like metal on metal, somewhat like clicking- which I assumed to be the read/write heads in the HD stuck.

I finally summoned the courage to open the ibook and replace the dreadful harddrive. Although painful to the fingertips, I managed my way through tight screws and small peices and successfully installed a replacement 30GB Fujitsu Harddrive. Upon reassembling the ibook, however, it still doesn't work. When I touch the power button, I hear the Macintosh chime, what sounds like the combo drive initializing, and I hear the hard drive spin as well. After a few seconds the screen will slightly/quickly flash blue three times, not a complete blue screen but a slight flash, so fast that it appears that only the middle of the screen is blue. After that there is nothing else. I set my ear close to the ibook to see if it is still on or not but I can't hear anything. When I press the power button the same exact results ensue; sounds from the cd and hd and the Mac chime followed by slight flickering of blue on the screen, so I assume it powers down directly after I turn it on.

Despite the fact that the ibook doesn't seem to stay on for very long, I attempted to put the system restore disc 1 that came with the ibook into its slot, but apparently I've made a mistake reassembling it because there is something blocking the disc from going in. Im sure its not another disc, because when I try to insert the disc I run into resistance in the front most corner of the drive, so I think a metal/plastic clip or something is blocking the way. This I will address after I have more information to go with as far as getting the ibook to work.

It's apparent to me that the hard drive was bad. After replacing the hard drive I no longer get the nasty metal grinding sound that occured every time I tried to turn the 'book on in the past. Now something else is preventing its function. If anyone has any ideas I would greatly appreciate it. I'm thoroughly determined to get this ibook working again.

Edit: to save some time for anyone who may reply, I have tried holding down shift after the chime for safe mode. Doesn't work for me, as the laptop is off again before it can do anything.