If Windows XP keeps rebooting, you have a few options to correct the problem and get your operating system back to normal. To fix Windows XP rebooting issues, try these simple solutions:
Perform a System Restore in Safe Mode
The first and easiest solution is to start your computer in Safe Mode and attempt to perform a System Restore. Start your computer. At the beginning of the startup, before Windows loads, press the F8 key to get a command prompt. You should have a list of options, one of which is to start the computer in Safe Mode. Select this option, and go into Windows Safe Mode. Once you're in Safe Mode, go to your Start Menu>Programs>Accessories>System Tools and choose System Restore. Here you can reset the framework of Windows XP to a time before you began having reboot problems.
If that doesn't work, try running System Restore in Safe Mode from a command prompt. Start up your system and press F8 before Windows loads to get the Safe Mode screen. This time, select Safe Mode with a Command Prompt. Once you get the command prompt, type %systemroot%\system32\restore\rstrui.exe. Press Enter, and you can try to restore your computer to a point before you had reboot issues.
Use Your Install Disc to Repair XP
One of the easiest ways to fix a Windows XP rebooting issue, depending on the cause, is to boot directly to the Windows XP Install Disc and repair your copy of XP. Insert your Windows XP Install Disc into your CD drive, and make sure your computer is set to boot to the disc before it loads the hard drive. Once you've successfully booted to the Windows XP disc, select the option to repair your Windows XP installation. Follow the on-screen prompts to repair your installation files. This can solve many problems.
If you don't get a repair option, or if the Repair Console isn't working, you can always do a fresh install of Windows XP without formatting your hard drive. Boot to your Windows XP Installation Disc, and follow the prompts to install the operating system without formatting. Make sure you choose to do this without formatting, as formatting your hard drive erases all of your files and data. Save that for a last resort, and try simply reinstalling your Windows files to fix your boot problem.
If All Else Fails...
The option of last resort is to format your hard drive and reinstall Windows. Keep in mind that formatting your hard drive erases all data, including program files, document files and software. Boot to your Windows XP Install Disc, and follow the on-screen directions to format your hard drive and reinstall Windows. This may take some time, but it should clear up any software problems causing your computer to reboot. If this last resort formatting option doesn't work, you may have hardware issues causing your computer to reboot, which can only be fixed by a computer service technician.
To install Windows XP SP3, or Service Pack 3, you can get SP3 through automatic updates or visit the Microsoft Web site. Either way, prepare for a long download.
Can you install Windows on a Mac computer? Yes, you can. Parallels Desktop will let you access Windows as a Virtual Machine, and Boot Camp software will let you choose between Windows and Mac every time the computer starts.