Some Sims are better than others. The "free" ones will help you develop 'thumb coordination', but that's about it. There are two that I know of that are better for learning because they emulate the real thing better than you might think; they are Great Planes "Real Flight" and another called "Aerofly Pro".

Both of these are expensive (at about $200 and $150 respectively), but offer a lot more realism, and parameters that can be set.
Dennis-