| Assuming you don't need to backup, firstly you don't say what model your machine is, or what the BIOS is, but you will need to ensure your machine can access a drive of 120Gb etc, there are ways and means around this, but assuming your machine is less than 5 years old it should be OK.
Remove the old drive, there should be a label on there which will have the drive setup as either a master, slave or cable select (CS), as it's your only drive it should be master. Install the new drive, and make sure the jumper setting matches the old drive (master etc)
Turn the PC on and enter the BIOS, you should see your new drive in the hard disk config, there may well be the option to set the boot order of your machine, if so set your machine to boot from CD first, then hard disk. Insert your Windows XP CD, and reboot. The PC should now boot to CD and installation wizard will guide you through the rest of the process.
Depending if the CD is an original, not a recovery disk, there will be the option to do a custom install, don't be afraid, this will walk you through the likes or partitioning your drive. I'd be tempted to have more than one partition, I have 3 on my 180Gb drive, C: 10Gb, D: 40Gb, E: 130Gb c: for the OS d: for games e: for music and when rendering DVD's etc. You could probably get away with 2 c: d:
Windows XP should have pretty much all of the drivers you will need, as long as you make a note of any drivers you might need, mainly being Video card, sounds card, network card, you should have a pretty good chance of doing this without too much trouble.  |