Okay, so I've been part of this forum for nearly a month now, I'm seeing the same issues and problems over and over again. So this topic is dedicated to anyone who feels like they are answering the same stuff over and over again.
You are running Windows Xp (Home or Professional)
Symptoms:
#1
Pc boots, but does not start Windows (you don't get any messages to insert boot disk)
You can see the Windows logo, but it doesn't go further than that.
#2
The pc is in a continuos loop, it starts and restarts, you can see the Windows logo.
For this symptom make sure that your hardware is firmly installed on your system(harddrive cables, ram, cd devices etc.)
Fix:
Go into Safe-Mode, press F8 as soon as your pc starts up, keep pressing F8, you will see a list of choices, choose the top one that says Safe-Mode
Click on your username when it has finished loading, after that click yes.
Go into My Computer and right click on your C drive, select properties, click on tools then click on check now. Click on Automatically fix errors(select it so that there is a check) and on scan for and attempt recovery of bad sectors. Click start. It will ask to check the system on restart of your system with a message like Windows needs exlusive access to some of the files on the disk, click on yes.
Restart the pc and wait for it to complete checkdisk, don't press any keys, just let it run. After the checkdisk your pc should work fine. While it's checkdisking have a cup of coffee or something!
If checkdisk did not work you can try a Xp repair install as described in this link:
http://www.michaelstevenstech.com/XPrepairinstall.htm