iMac 24" running very slow

Hello

I've got 2 issues here and searched through the forum but couldn't find complete answers to my issues.

1. My 24" iMac died. When I tried to start it up, it would get stuck on the start up screen which was gray with the apple symbol and a status bar. Then it would automatically shut off after a minute.

After reading some forums, I re-installed Snow Leopard and that seemed to work because I can now get on my computer, but I have to re-install all programs and such. The new issue I'm having now is this: When I re-installed Leopard, the message said the program could not be installed on the "built in" Mac Hard Drive. I had to install the program on an external hard drive for now.

I'm now using disk utility to try and repair that hard drive. I hit "Verify Disk Permisssions" and these are the messages I receive:

Permissions verification complete

Verifying volume Macintosh HD
Disk Utility stopped verifying Macintosh HD
Could not unmount disk

Repair Disk Permissions did not come up so does that mean I need to Erase everything and start from scratch? I will back everything up before I do that if that's the case.

2. Prior to all this, my computer was running really slow and I believe it's due to memory? It says the Capacity is 249.2 GB, there is only 30.25 GB available because I've used 218.95 GB and there are 1,544,933 files.

I have removed "or so I thought" all the apps I don't use to try and free up some space. I also bought the app zapper so if when I removed those programs, every file attached would follow. This didn't do much and there seems to be files behind the scenes which I have no idea how to retrieve to clean out.

Any suggestions on how to free up more space so the computer isn't so slow when running some of my programs? I use Lightroom and Photoshop together a lot and I'm literally waiting 1-2 minutes in between each picture to open/save. It's ridiculous.

Any guidance or advice would be GREATLY appreciated!!!!!

Thanks in advance!!!!!!
Melissa

Hi Melissa:

Welcome to the Mac Forums.

The symptoms you describe are typical for a dying hard drive. It may be too late now, but If possible, backup whatever you can from the hard drive.

The hard drive needs to be replaced and that is not an easy task to do on an iMac since the entire display front panel must first be removed to access the inside of the machine. If you're a handy do it yourself person, you can look at the instructions for removing and replacing the hard drive at iFixit: The free repair manual.

Otherwise, take it on in to an authorized Mac repair or Apple store and have them replace the hard drive. Be sure to get an estimate first before letting them do the work. If you have any more questions, post back to this same thread.