Computer won't turn on?

Hello,

My iBook one day decided to stop working. I would turn it on, but you could only hear the computer working and nothing would show up on the screen. I took it to the genius bar awhile back and they hooked it up to an external monitor, but it still didn't work. They asked for $300 dollars to send out the computer, find out it's problem and fix it. I decided not to do that.

Recently, my uncle gave my iBook to his friend who is a professional at fixing macs and he took a look at it and even took it the mac store for a look. Apparently the mac store said the problem wasn't the logic board, but the hard drive. I had a 30 gig hard drive on it that was maxed out.

At any rate, I went and bought a 250 gig hard drive as per his specifications and this website's and installed it. However, the computer is still doing the same thing. Very rarely do I hear the "gong" sound in the beginning. I put what I thought was a boot up disc in the optical drive (it was actually an upgrade a disc) and it got stuck and wouldn't come out. I had to dissemble the computer again and open the optical drive to take it out. Now I have put the parts back and I am trying to put in the leopard boot up disc inside, but my optical drive won't except it.

I'm really stuck on what to do, does anyone have any suggestions?

Also, I accidentally pulled on the optical drive orange ribbon clamp a little too had and the ribbon came out without me actually taking the clamp off first. I put it back together, but do I need to get a new ribbon clamp?

Thanks.