MacBook not booting

My MacBook is not booting. I put it to screensaver mode and after a while touched the trackpad to log back in, but the small little beach ball showed up, it didnt stop and after about a minute I manually shut down it down (pressing power key for about 5-6 seconds).

I rebooted and first the gray screen with the Apple logo shows, a little circular motion showing something is going on appears, then a plain blue screen appears, the same circular motion thing appears, but then it just keeps doing that.

I inserted the Mac OS X disc that came with the notebook and it still doesnt do anything, just rev's up in spinning and then winds down.

If anyone can help me with solving this problem I would really appreciate it.

Thank you.

 

Put in the Leopard disc, then hold in Alt during restart. That should then bring you to a screen where you have the option to select which medium to boot from.
Did you install any 3rd party software between when you last restarted your Mac, and when you went into screen saver mode? Some applications use hacks that are incompatible with Leopard, and therefore causes problems when you try to start the computer. The easiest way to fix this is to reinstall Leopard, unless you can somehow get into OS X and uninstall the hack.

 

Thanks for your advice. I didnt install any software or install any software updates like I found on the internet with other people who had similar problems. I just held down the "c" key to boot from the Mac OS X disc that was already inserted (the one that came with the notebook) and it booted from the disc, and I reinstalled Leopard, everything setup to my personal preferences in about an hour.

I'm still not sure why this happened but its no big deal now. Thanks again.