If a disk has got encrypted files, you are automatically asked for a password when you try to access it. 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.