Assuming they were willing to continue the experiment, what goes for median level of proficiency shouldn't be that difficult to achieve in a short time. They would probably be better served learning how to operate or program a 1986 era computer. They could still learn about Unix, Lisp, Smalltalk, C, spreadsheets, word processors, (La)Tex, etc. After being exposed to that stuff, they might even be disappointed when they get access to contemporary technology.