omgpancakes,
The preload and factory would not apply in your situation. These are used by large OEM's to preload PC-Doctor on systems for customers to use and to build systems in the factory.
Service Center would be the product for you. There are two kits to choose from, Standard and premier. The standard kit includes a minimum of hardware, basically loopback devices and is lower cost. The premier kit includes the POST cards Standard and mini PCI and Power supply tester, it is $120.00 more to cover the cost of the hardware.
In your situation I would get the regular Service Center kit. Free software is always an option and the price is hard to argue with but you get what you pay for....
-Fred