No matter what kind of computer disk it is, it'll be readable by any system you put it into. All application software is usable by all computer platforms. The more high-tech the equipment, the more buttons it has. However, everyone must have been highly trained, because the buttons aren't labeled. Computers never crash during key, high-intensity activities.
Humans operating computers never make mistakes under stress.
A custom system with millions of lines of code controlling a multimillion dollar theme park can be operated by a 13 year old who has seen a Unix system before. Knowing an operating system means you know how to run any application on that system, even custom apps. You cannot stop a destructive program or virus by unplugging the computer. Presumably the virus has it's own built-in power supply. You cannot stop a destructive program downloading onto your system by unplugging the phone line.