I don't know why you would think that. The Quran states:
Behold, those who are bent on denying the truth and on evildoing - God will indeed not forgive them, nor will He guide them onto any road. (4:168)
And whenever there came unto them a [new] revelation from God, confirming the truth already in their possession-and [bear in mind that] aforetime they used to pray for victory over those who were bent on denying the truth -: whenever there came unto them something which they recognized [as the truth], they would deny it. And God's rejection is the due of all who deny the truth. (2:89)
Verily, it is We who bestowed from on high the Torah, wherein there was guidance and light. On `its strength did the prophets, who had surrendered themselves unto God, deliver judgment unto those who followed the Jewish faith; and so did the [early] men of God and the rabbis, inasmuch as some of God's writ had been entrusted to their care; and they [all] bore witness to its truth. Therefore, [O children of Israel,] hold not men in awe, but stand in awe of Me; and do not barter away My messages for a trifling gain: for they who do not judge in accordance with what God has bestowed from on high are, indeed, deniers of the truth! (5:44)
Verily, those who [despite all evidence] are bent on denying the truth - [be they] from among the followers of earlier revelation or from among those who ascribe divinity to aught beside God - will find themselves in the fire of hell, therein to abide: they are the worst of all creatures. (98:6)
What you would recognise from the Quran is that Kufr - or disbelief - is the active and continued rejection of God's "clear signs", which are supposed to leave no room for any doubt. It is for this reason that the kafir is NOT A NON MUSLIM, but a "concealer". The other meaning of a "kafir" in the Quran is those who historically prevented Muslims from following their religion by persecution.
And the inmates of paradise will call out to the inmates of the fire: "Now we have found that what our Sustainer promised us has come true; have you. too, found that what your Sustainer promised you has come true?" [The others] will answer, "Yes!"-whereupon from their midst a voice will loudly proclaim: "God's rejection is the due of the evildoers who turn others away from God's path and try to make it appear crooked, and who refuse to acknowledge the truth of the life to come!" (7:44-45)
Shirk, on the other hand, is understood by some as idol worship after the message of God has become undeniably true, or those who set up idols of men (ie, hold their own brethren at the level of God):
AND WE BROUGHT the children of Israel across the sea; and thereupon they came upon people who were devoted to the worship of some idols of theirs. Said [the children of Israel]: "O Moses, set up for us a god even as they have gods!" He replied: "Verily, you are people without any awareness [of right and wrong]! (7:138)
And, lo, Luqman spoke thus unto his son, admonishing him: “O my dear son! Do not ascribe divine powers to aught beside God: for, behold, such [a false] ascribing of divinity is indeed an awesome wrong! (31:13)
VERILY, God does not forgive the ascribing of divinity to aught beside Him, although He forgives any lesser sin unto whomever He wills: for he who ascribes divinity to aught beside God has indeed contrived an awesome sin. (4:48)
You don't seem to fit any of these descriptions, do you?
What you also ought to remember is that movies, magazines, and books come centuries after Muhammad and his claim of Prophethood. There is therefore nothing that PROHIBITS you from reading and watching anything in the Quran, but you may infer that something - eg. pornography or even terrorist propaganda - may not be good for you. The Quran exhorts you to think:
Verily, We have shown him the way: and it rests with him to prove himself either grateful or ungrateful. (76:3)
Therefore, if you choose to disassociate with someone or something simply because of their different beliefs is unjustifiable. The Quran tells us:
As for such [of the unbelievers] as do not fight against you on account of [your] faith, and neither drive you forth from your homelands, God does not forbid you to show them kindness and to behave towards them with full equity: for, verily, God loves those who act equitably. (60:8)
Therefore, if Muslims are told that they can love and be kind with non Muslims - who follow a way different from Islam - and still remain Muslim, then what makes you think watching a movie could change you in the eyes of your Lord, whose children we all are? On the other hand, you could make a conscious decision not to watch something immoral, such as material encouraging violence, racial hatred, or complete nudity. It is up to you, but don't fall into the trap of believing extremists who cannot justify their false claims with the Quran.
May God bless you and establish peace in this world. I hope this answered your question :)