System Idle is 00 - extremely slow computer

I am using a Dell Inspiron 1000 with Windows XP, SP3. When you turn the computer on it boots normally to the user screen. Once you click on the user screen, that is when everything starts slowing down. If you can get to the task manager window, it will show that the computer is at 00 idle speed. So this is what I have done so far. I have run virus scans, none found. I ran a scan of the hard drive and it showed no problems. With this I did F12 at the startup and selected the drives option. Then I did the same thing, F12 at startup and then selected the diagnostics scan and found problems with the IDE hard drive, error codes such as 0F001A44 and many others related to the IDE. The CPU and fan all check out fine, as I was suspecting there was a heat problem slowing the computer. When I open the computer in Safe Mode, everything runs at the normal speed. (I just had it in safe mode and copied all of the files to an external hard drive). I suspect there is a hard drive problem and it probably needs to be replaced, but I don't understand why the hard drive isn't affected during safe mode. Any suggestions? I suspect my friend does not know where her Windows disks are, so hoping that maybe there is a fix.

I forgot to mention. This all started about 2 weeks ago, getting the BLUE SCREEN. Then it would seem like the computer would run fine, and then the BLUE SCREEN would show up again.

Also, when looking at the task manager processes tab, when the idle speed is 00, usually the services.exe is very high, like in the low 90's. The taskmgr.exe takes a bit and sometimes if the antivirus is running. But almost always a very high number on the services.exe. I don't know if this is at all connected. Is that file corrupt? Can it be repaired or can you take a services.exe file from a working computer and replace that file?

Here is a program called Process Explorer. Go get it and use it. Configure it to show some fields like Path and Command Line. It will show you what's running, where from, and how it began. Then you can kill the offending process(es) and fix the files where they are coming from. Chances are good that there's some malware/virus/etc. that you didn't know you had making life hell for your compy. Check out our sticky thread in the virus forums for help on fixing it if you find that is the case.

Can I do this in Safe Mode? The speed is so slow I probably wouldn't be able to get to any of those programs in the regular start-up. I got the Process Explorer zip loaded onto a thumb drive, but then the computer couldn't extract the files. So I did the extracting in Safe Mode and it did, of course while in Safe mode, everything is okay.

Do a thorough malware and antivirus scan.

I shouldn't have used the phrase everything is okay. When in Safe Mode, there is no 00 idle process, it is usually around 99 and so seems to run just fine and so I wasn't seeing anything to check with the Process Explorer. I need to go back and do that in Safe Mode anyway, I guess.

Right now I am in Safe Mode and I ran the CC Clean and ran the Malwarebytes. It just completed the Malware and it showed 57, so will remove those per the instructions. I copied the log and then did a restart and no change so far.

ATF Cleaner link doesn't open into a window.

Am going to run the superantispyware now.