Does anyone have any more answers?
Start with Tie Fighter: it has plenty of tutorials, difficulty levels (selectable in the options menu recalled by pressing ESC on the main inferface) and cheat options that while they deprive you of points IIRC do not block progression.
X-wing is NOT recommended if you worry about difficulty, even with the manuals the game is much more opaque and the mission design is often rather unfair, if you are going to try it I suggest you do after Tie Fighter.
Only keep in mind that the tutorials and training aren't incorporated in the main campaign ("battles") but in sections called "Combat Chamber" (which also allows to replay the missions from the campaign you already unlocked) and "training simulator".
The CD versions comprised in the GOG and Steam package also have a handful of save files with everything already unlocked (the same is true for X-wing but the other points a about difficulty still stand).
Also I suggest you use the DOS cd version as the windows CD version at times is more difficult.
The other good point to start is X-wing Alliance but I always got the impression that it doesn't as good a job for new players and it doesn't help that you need to use a workaround for playing with a mouse if you don't have a controller like all the windows games in the series.
X-wing vs Tie Fighter has some balancing issues, while it has plenty of single player content it is balanced primarily for multiplayer and that makes it more difficult than TF and XWA, but still more fair than X-wing somehow.