iMac very slow to respond

[ghostrider501]

Hi, I have a late 2010 model, 27" IMac 3.6 i5.

Over the last few weeks I have noticed, at times it was slow to respond but then it would work away as normal.

But now in the last 2 days, sometimes it will not start up, stays at the apple logo screen with the spinning progress bar.

And if it does start, it's unresponsive and just unusable,

Things I have done:
Booting Disk Utility from cd drive and tried to Repair Disk,
It came back by saying, errors could not be repaired.

I ran, Apple Hardware Test, it got to about 90% and it just seemed to freeze and never finished.

So I was just wondering, would anyone be able to give me some advise, on what the problem might be and what I should do next?


Two questions to do with backing up, before I try anything else I'm going to try and backup my hard drive using and external hard drive.

Is backing up to an external hard drive using Time Machine the best option?

At the moment, If there are files on my hard drive that are corrupt or cookies or caches or whatever it is that might be causing this problem,
Well if I back everything up to a new hard drive and then if I have restore from that hard drive in the future,

Am I just reinstalling the infected files back onto the system?

Any advise would be really appreciated,

Sorry for such a long post,

 

[derbothaus]

You need to repair the disk. Get a copy of DiskWarrior and your life will be all better. Seriously. It is not the files it is the hard disk directory as stated in the failure when you ran Disk Utility. Everyone should have a DiskWarrior copy anyway.

 

[ghostrider501]

You need to repair the disk. Get a copy of DiskWarrior and your life will be all better. Seriously. It is not the files it is the hard disk directory as stated in the failure when you ran Disk Utility. Everyone should have a DiskWarrior copy anyway.

Iv heard of DiskWarrior before,

Is it really that good?

What do you think was the cause of this to happen?