Many HP/Compaq computers have instructions you can get to in Help & Support,
by searching for something like create recovery cd; these computers
typically have the hard drive partitioned into a large partition for the
user (typically C: drive), and a smaller recovery partition which may be
hidden or may show up as drive D:. Some computers include a set of recovery
discs. Some Dell computers included an slightly modified Windows
installation CD -- it would install the OS without requiring the product key
on a wide range of Dell computers. Most computer manufacturers allow you to
purchase a set of recovry disks. HP.com typically charges under $20. It is
the responsibility of the computer builder to provide a method of recovery.
If you post more info on the source/type of computer you have, perhaps
someone can give more specific instructions.
-Paul Randall