Follow these instructions to do a fresh install. You will lose all that is currently on the Partition that has the OS. Once you do this you will need the Motherboard drivers so keep that in mind. If this procedure fails to work than you have a bad CD, A bad drive or some other hardware failure.
New/Clean Install/Re-install
The full install OS/CD is required for this procedure.
1=Set Bios to boot from CD/ROM as first boot device(Entering commands for the BIOS will vary depending on the computer, Most will use the Delete key. you may have to refer to the computers manual for this).(For a clean or new drive the boot sequence does not matter)
2=Place the OS/CD in the CD/ROM drive and Re-Boot
3=Watch for the prompt to "Press any key to boot from CD/ROM" Press ASAP (Ignore when prompt appears on any reboot) (You will only get this prompt if there is an OS installed).
(A) If SATA drive watch for prompt to load drivers
4=windows Setup (Loads Files)
5=To setup XP now press "ENTER"
6=Press F8 for license
7=To continue installing a fresh copy of windows without repairing press "ESC"(You will not get this prompt for a new or unpartitioned drive)
8=For a new or unpartitioned drive press "ENTER" (or you can press "C" if you want to create multiple partitions).
9=For a drive that has partitions, operating system or any data on it, you should press "D" to delete the partition and start out with a clean drive
.
10=Press "enter"
11=You will be prompted again, press "L"(You will do this for each partition) , Now you are ready to partition and format
12=Press "C" (Only if you want multiple partitions, Otherwise press "Enter"
13=To setup windows on the selected partition press "enter"
14=Select-format the partition using the NTFS file system
15=Press "enter'
16=Wait for format to complete
17=Computer will start copying files to the installation folders (this may take several minutes)
18=Computer will re-boot, do not press any key to boot from CD/ROM when prompted
.
19=follow the on-screen instructions to complete loading windows.
{NOTE}
If you want to format the entire "C" drive Or the "C" partition where XP is installed, You can also do the following:
1. Start Computer booting from OS/CD
2. Choose Recovery Console (R)
3. At the dos prompt type: "format C:" (without the quotes)
4. If it asks for the "Administrator Pass Word", Type it in if you have one or just hit "Enter" to continue, If that does not work you will not be able to use the recovery console unless other methods are used to change such.
5. Commands that you can use, format (drive Letter)/ Q (quick) FS/ (File system fat/ntsf)
I have a dell dimension 4100 900mhz 256mb sdram. i have it about 1 and a half. My warrant is up. The problem is i purchased a window xp cd. When i tried to install it it loaded ok i pressed f8 to agree with condition. When it star to copy files i get computer cannot read disk put a valid disk in computer to continue setup. I remeber having a similar problem when i was testing a friend computer someone gave him by installing windows from his computer cd which was a SATA harddrive on a computer with a ata hard drive. My computer is an ATA hard drive could the cd be for a SATA hard drive or it doesnt matter.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic