Spinning multi-coloured disc

.. generally speaking the spinning disk means your computer is overloaded and busy doing other more critical stuff.

Some have said in this thread it may be the symptoms of a bad disk. That might be true, then again it might not. Your machine is getting old and that might lead some to believe the disk is ready to go. Suggest you first back-up your critical files or documents, then run Disk Utility to Verify the Disk and then Repair Permissions. If it is a disk problem you can buy a new disk very cheaply from macsales.com . They even have instructions on how to install it.

You may want to consider upgrading your memory. You can check to see if you are maxing out your memory thru a utility called Activity Monitor. This could be another reason why you are getting the spinning disk. Without getting too technical.. if you have a lot of applications that require more memory than is available on your machine to run these applications, the Computer swaps applications that are less important in and out to disk to make room for the applications you want to run that are more critical. IT takes time to do this, hence the spinning disk.

If your machine is an old PPC based iMac, it may be time to erase and re-install your Mac OS 10.5. Do you have the original Apple disks that came with the machine? You will need these disks to do a fresh installation of MacOS. If not, you'll have to call Apple Customer Service and get original replacements.

That should cover it.. When all else fails, take it to the Genius bar in an Apple Store.

Of course, but, I mean, as Mac OS X is an UNIX-based system, the first thing he should do is to repair the disk's permissions (I don't know if it's said like that at the English version, I use the Spanish one).

To verify and repair that, the only thing you should do is to go to the disk utility, and, run the permissions verification test.

Repair Permissions only makes a difference on a healthy backed up system with an update that doesn't set the permissions back. We have neither determined the health nor the status of the backup yet. Please be patient for those to be determined before offering advice otherwise.

The g5 is not an Intel, the Intel is more a g6 though Apple never called it that. Go to Apple menu - About This Mac to tell if you have a g5 or Intel. White iMacs may be both.

Go to Disk's Utility at the utilities folder at the applications folder and check if your hard drive is ok.

By both I mean either or...you either have a g5 or an Intel.

Next I would need to know if you are backed up at least twice.

Once you tell me those two facts, we can offer some suggestions.

A little early to do that. Examinng failing drive may speed its demise. Getting as much data off safely is our first priority.

And your drive my not be failing but we can't tell the difference without risking your data, which is why I say it is too early.