Os wont work

Hopefully it is a software problem, and not a piece of hardware that is faulty and hanging up the boot procees.

You probably should do a complete software restore.

WARNING>>> This will erase all new information on your computer. Any new files, folders, pictures, etc., that you have aquired will be lost.

Dell Windows Vista Recovery from Factory image

Start the computer. As the computer starts, press the F8 key until the Advanced Boot Options menu appears on the screen. Press the (Down Arrow) to select Repair Your Computer on the Advanced Boot Options menu, and then press Enter. Specify the language settings that you want, and then click Next. Log in as a user who has administrative credentials, and then click OK. Click Dell Factory Image Restore. In the Dell Factory Image Restore window, click Next. Click to select the check box for Yes, reformat hard drive and restore system software to factory condition. Click Next. The computer is restored to the default factory configuration. When the restore operation is completed, click Finish to restart the computer.

Stoped at the 4th step before it would take me to the page to specify language it took me back to the begining.  Ive also tried the safe modes and they just do the same thing.

Is there a way to reset the computer without having to go any further?

See if you can get that system into the diagnostic mode. I believe on that model, you press F12 on on startup after you see the Dell Logo, then choose diagnostic mode.

If you can't get it into diagnostic mode, then see if you can get into the bios... Select F2 at the startup. If it goes into bios,  just leave it there for a few minutes and see if it stays in bios without re-starting.

Starting to sound like a hardware failure. Maybe a hard drive failure, but need more info.

I can get into both of them and it will stay there.It dosnt restart ive also ran most of the diagnostics and all pass its showing nothing wrong.

Before it did what it did the only problem was when I opend like 2 windows in Internet Explorer it would come up low memory. Ive also ran the Memory test and all passed.

Still Had like 300 Gigs outa 500

No Viruses well none that the antivirus diddnt find

Seems like one of two things. A virus, or a bad hardware driver that is resetting the computer as soon as the driver loads on startup.Although you would think that the driver problem was ruled out when you couldn't boot in safe mode.

I would take the Hard drive out, put it in a usb enclosure, and virus scan it with another computer. You could also use a bootcd with antivirus on it to scan you computer.

Seems like one of two things. A virus, or a bad hardware driver that is resetting the computer as soon as the driver loads on startup. Although you would think that the driver problem was ruled out when you couldn't boot in safe mode.

I would take the Hard drive out, put it in a usb enclosure, and virus scan it with another computer. You could also use a bootcd with antivirus on it to scan you computer.

Thanks, So all should be well if I go get a new hard drive for it?

Not sure yet. Trying to troubleshoot.

If there are no important files on the computer that you are afraid to lose, you could do a clean install using the backup disc.

Just choose the option to completely format the hard drive. That should get rid of any viruses.

If its a virus problem, you should be able to do a clean install from the restore disc.

If it won't do the install, then we will know that it is a hardware problem.

If you had a spare harddrive, you could use it. Just put it in, and see if you can do a fresh install from the backup disc.