Not necessarily all of it, but some. For example, processor information is found in HKEY_LOCAL_MACHINE/HARDWARE/DESCRIPTION/System/CentralProcessor/0/ProcessorName String.
I am in the process of designing a Java program for a Computer Science dossier. I am planning to create a program that reads hardware and software information from the registry and organizes this data into a database, where you can add and remove systems. It would probably resemble the CPU-Z...