The reflexes of a human in our stage of evolution might not be ready for the kind of quick responses it would take to dog-fight in space. However, a medi-evil knight would not have the reflexes or mental capacity to fly a modern day fighter jet, either.
As our society changes we evolve. Years ago it would have taken a genius to operate or especially program a computer. Now, however, a reasonably intelligent grade-schooler can operate a computer and that same reasonably intelligent person by junior high can do basic computer programing.
On the other hand, a medieval knight would totally own you in combat, and you wouldn't have the faintest clue as how to joust properly.
Years ago it took a genius to operate a computer because computers were as big as a typical house. Now you have point'n'click, easy enough that almost anyone can pick it up in a few days. Computer programming has also gone down in complexity, depending on what language you are using. VB.net for example, is pretty easy. Coding in Assembly is not, however.
First of all, I do have the slightest clue how to joist properly. However, that is not the point.
A person from that time period would not have the mental capacity to use a computer because they did not grow learning things that would perpare them for it.
This is also the same reason why the elderly have a difficult time with new technology. It is called evolution. We grow in comparison to our enviroment.