As other replies have mentioned, this can easily be done with the software
that come with the "retail" version of the new hard drive. They have
mentioned GHOST, run form a floppy, whihc I have also used with good luck.
Another possibility is Acronis True Image, which runs from a bootable CD,
instad of a floppy. Handy if you do not have a floppy drive.
As for a repair installation of XP, that is normally not required for a
simple disk upgrade. The exception would be if you switch from IDE (also
called ATA) to SCSI or SATA drives. Then a repair will definitely be
required. To run a repair, you will need a retail copy of XP, full or
upgrade. See the following links on repairing:
http://support.microsoft.com/default.aspx?scid=kb;en-us;315341
http://www.webtree.ca/windowsxp/repair_xp.htm
http://www.extremetech.com/print_article/0,3998,a=23979,00.asp
If you have a retail copy of XP, changing the hard drive will count as one
change towards having to re-active XP. If this is the only hardware (or
BIOS) change you have made within the last 3 months, you should not be asked
to re-activiate. But, if you have replaced RAM, video, etc and then do this
hard drive, you may need to re-activate. That is not a big deal, even if
you are told (on the screen) to call an 800 number. Just explain what
changes you have made.
If you have an OEM copy of XP, those are usually locked to the BIOS, so you
can freely change any hardware, except the motherboard, without
re-activation. But, some OEM CDs do not support a "repair". If OEM (e.g.,
Dell, Gateway, Compaq) check with the PC maker bfore swaping the hard drive.
Note that some OEM CDs do not contain XP at all! Instead, they contain a
small recovery program that works with an image of the original hard drive
that is contained on a "hidden" partition. Such a recovery CD will not work
with a new hard drive, and will not uppot a "repair" of XP.