if you would like to format and install windows to a new hard drive (as well as reformat and reinstall windows to an old hard drive) just follow these steps.
1. enter computers BIOS ( enter by tapping the button specified on your screen. it should say something along the lines of "hit __ to enter BIOS" or "hit __ to enter setup.") almost every make is different.
2. while in the BIOS, select something along the lines of "boot order" or "boot prioity." (again almost every make is different)
3. make your cd drive boot first. (by setting it in the first slot)
4. save settings and quit (comp should restart)
5. your comp will now boot off of the windows cd
6. follow the onscreen instructions that the windows cd supplies
and remember, format means it erases EVERYTHING!
if any of this is confusing, tell me where i lost you and a will clarify.