A) If you don't have Floppy Disk Drive especially on a notebook. You still can install Win Xp but you need to read the "Slipstreaming SATA driver into WinXp boot cd using nLite".
B) If you have FD drive, skip this step and go to "Shrink Vista Partition for WinXp Installation".
C) If you have an empty partition for WinXp installation, proceed to "WinXp Installation"
1) nLite(download here), a free tool to help you slipstreaming(integrate) your SATA drivers into WinXp installation disk.
2) Extracted SATA drivers(if you are using Intel chipset Intel 82801GR/GH, 631xESB/632xESB, 82801GHM, ICH8R/ICH9R, 82801HEM SATA RAID Controller, get the drivers from here)
1) Get your Windows XP installation disk and copy the contents to a new folder(I named it "WinXp").
2) Extract the SATA drivers you downloaded into a folder, namely "Floppy 32Bit". (Need help for "Extracting SATA driver from their EXE without Floppy Disk(FD)")
3) Run nLite->choose "Next".
4) Now, locate the Windows folder(for me, it's "WinXp").
5) Next again and you will come to "Presets". Ignore this by choosing "Next" again.
6) In "Task Selection", choose "Drivers" and "Bootable ISO" by high-lighting them.
7) Choose "Insert"->"Single driver"
8) Browse to the SATA driver folder(I named it "Floppy 32Bit") and select either one of the .INF file, I choose "iaahci.inf".
9) A screen like below will pop-up, make sure it's "Textmode driver" and select all of them by holding CTRL+A key and choose "OK"
10) You shall see something like this. Choose "Next" and you will be prompted.
11) Choose "Yes" to start the process.
12) Let it finish and choose "Next".
13) Finally, you can create your project as ISO image or burn it directly to CD-R under "Mode". I choose "Direct Burn". You can put anything for "Label" but not too long. Choose "Burn" and you will be prompted again.
14) Choose "Yes" to burn it to CD-R. Wait for it to finish and choose "Next"
15) Choose "Finish" to exit nLite.
A) Go to "Shrink Vista Partition for WinXp Installation" if you don't have any partition to use.
B) If you have an empty partition for WinXp installation, proceed to "WinXp Installation"
Ref : http://maxeasyguide.blogspot.com