Won't boot past blue screen.

If it boots happily in safe mode, I woud boot from your install disc and use Disk Utility

1. Insert the Mac OS X Install disc that came with your computer, then restart the computer while holding the C key.
2. When your computer finishes starting up from the disc, choose Disk Utility from the Installer menu. (In Mac OS X 10.4 or later, you must select your language first.)
Important: Do not click Continue in the first screen of the Installer. If you do, you must restart from the disc again to access Disk Utility.
3. Click the First Aid tab.
4. Click the disclosure triangle to the left of the hard drive icon to display the names of your hard disk volumes and partitions.
5. Select your Mac OS X volume.
6. Click Repair. Disk Utility checks and repairs the disk.




Let us know results, please.

If MGW's suggestion does not work.........



If you found no solutions to your problem(s) listed in the various Knowledge Base Articles see if the following suggestions are of any help:

Except for the keyboard & mouse, disconnect all devices/peripherals from your computer.

Step 1: Restart into Safe Mode by holding down the Shift key during startup. The comp will run a complete & lengthy file systtem check, then start up w/only the required kerenel extensions & w/o running any Startup items that you installed.

Try starting up normally again. If you are still stalling, restart in Safe Mode & move on to Step 2...........
Mac OS X: Starting up in Safe Mode

Step 2: Open Library>Startup items folder-the root level Library, not the one in your user name folder.
Look for potentially problematic 3rd party items such as virus scanning software components, etc. Remove 1 or more items to a location outside the Library folder, such as the Desktop, then restart normally & see if your Mac stalls. It it does, try removing all the items in the Startup items folder & restart. If all’s now well, place the items back into the Startup items folder 1 by 1, restarting each time you put one back. If and/or when the stall resurfaces, you just identified the faulty component.
If the above does not work, then it’s time to move on to Step 3.................

Step 3: WARNING-This step can be tedious-removing .plist files from the /Library/Preferences folder.

Remove the entire Preferences folder from the Library folder on your startup drive then place the files back 1 by 1 until you see the problem return. *The Mac will automatically create a new Preferences folder in the Library folder*
Alternatively, you can take half of the items out (all non-Apple .plist file, for example), restart to see if your Mac stalls, then move to a smaller set of items, repeatingn the process until the culprit is found.

Or you can use Preferential Treatment which is a FREE utility that does all the work for you.

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After your problem is resolved, you should seriously consider updating your OS to v10.5.8. which from memory is the last Leopard version. Use Software Update to update all the other stuff that goes along w/the updated OS.





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Or you can use Preferential Treatment which is a FREE utility that does all the work for you.

Applejack also will check for corrupted Preference Files. But it needs to be run in Single User Mode. And AJ is a good troubleshooting tool for a lot of problems.
http://applejack.sourceforge.net/#top

If my memory is not faulty here, I've also seen a number of reports of blue screen problems for MacBooks. You could google for those.