OS reinstall questions

I’m planning to redo my HDD and have a few questions about reinstalling XP:
Once I complete the primary install process from my “Setup Disks” my system will have XP Home and most of my applications installed … at this point I usually start “updating” things and would download/install SP1, etc. until I’ve updated the system to SP2.

I have SP2 on CD … does that CD also contain all the updates that were part of SP1 (and everything in between?)

Do I need the updates from SP1 or can I go right to SP2?

Is it possible to get SP1 on CD?