Ioannis,
I appreciate your point of view, and you know certainly that I hold you in high esteem; I think that certainly most acting these days is part of a wide system of immorality. However, I would like to politely engage you on this point.
In regards to those canons, I am of course aware of them and probably should have anticipated their being brought up and explained why I did not think they applied to this situation. Acting and in fact most entertainment in that time involved prostitution, nudity, and making sacrfices to the emperor. Hence, there was simply no way that one could be an actor and be a Christian. Before the conversion of St Constantine--and in fact, up until the time of St Theodosius the Emperor, it was impossible to be an emperor and a Christian as well, which explains why St Constantine delayed baptism. St Theodosius, being forced into the situation, tried his best to make it work which invovled changing a lot about the office of emperor. In the same way, a lot has changed in theatre since those times as a result of the entire culture being gradually Christianized--a process which as we know is now unraveling. The point is there are always these two tensions and one must make a judgment as to which one is the prevailing trend in any given action that we do that is gray (ie not sinful per se and not good per se, such as relaxation, going out to eat, playing a game, exercising, etc). A good restaurant could be a valid time for relaxation (even St Anthony the Great played leap frog and such games with his monks) or it can be a temptation if one indulges in gluttony and drunkeness.
In the same way, movies can be used for Christ, can be used for relaxation that is neither bad nor good, or can be used for evil. I believe that movies like the Passion of the Christ fall into the former, and many artistic movies that are certainly not immoral fall into the middle category, and that the vast majority of modern American movies fall into the latter (although there are some exceptions).
I personally believe that it's best to avoid movie theatres so that if a movie begins to turn immoral it is not hard to leave especially if with friends. If watched on DVD for instance one can certainly turn it off. Also, the exorbinate rates that one pays to see a movie these days borders on sinful indulgence.
At any rate, acting is a cultured profession if used for God's glory or at the most for relaxation. It's not any different than being a mayor or a politician, which many Orthodox participate in. You can do it for God's glory or for evil. A good actor can star in roles that push forward knowledge of Christ, Christian culture, themes of good and evil, etc. I see it no different than Dostoyevsky writing novels in his time.
Let's remember that at least one bishop we both know had his monks watch the Passion of the Christ, and the ones starring in this movie were all actors.
So I would certainly agree with you that most of the movies today are immoral and should be avoided, but I believe that Orthodoxy teaches us how to make moral choices, unlike RCism which tends to give you a drawn out black and white definition of everything. If you want to say it's better not to watch movies, I would generally agree. We should all be praying more. But when it's time to relax or when one wants to see a positive message reinforced or when one wants to see artistic elements a wholesome movie is ok and hence being an actor that participates in these films is justified.
Yours in Christ,
Anastasios