If you know someone who has already d'loaded SP2 get them to burn a CD for you; it can then be copied to your hard drive to allow you to make the slipstream. Alternatively look for a free SP2 CD on PC magazines covers, might still be some kicking around.
If you can't create a slipstream, for a fresh install of Windows the normal batting order for installation is:
1. Windows XP CD.
2. Chipset/AGP drivers.
3. Latest DirectX.
4. Video drivers.
5. Anti Virus.
6. 3rd party software firewall (if used).
7. Online Windows Critcal Updates (including SP2).
8. Other device driver updates.
9. All other updates.
Make sure you have downloaded all the latest drivers you need and burn them to a CD to use during the install.
The install procedure is very simple. Just put in your original MS XP Home CD and boot from it. During the installation the CD will give you the option to format your drive. Select yes and that will erase all previous data on the drive (hence the need for an offline drivers archive).
Hope this helps.
TOG