I highly doubt we'll ever get any ASOiAF movies, much less one to tie-up Game of Thrones. Maybe we'll get a feature-length finale on HBO at the end of Season 7 or in place of a Season 8, but a self-contained feature film it will not be.
My guess for how the show will wrap-up:
end season 5: danny gets her new Khalisar. battle for mereen starts. Showdown in Dorne. Bron dies. Jamie is captive. Arya reaches adept stage of her training. "for the watch" happens. Stannis is empowered with some kind of serious fire magic (possibly dragons), but which wont get used yet. Breanne dies but not before helping Sansa escape. Sansa is sprung and flees Winterfell. winter gets closer...
start season 6: danny returns to Mereen and finds it under siege. She, her dragons, and her new khalisar pretty much lay waste to everything. Jon comes back a la Beric Dondarion and takes some form of revenge.
mid season 6: however danny gets her fleet and ties-up her events in the East, she does so during the bulk of season 6. Also, the bulk of Season 6 consists of Jamie getting himself and Myrcella out of Dorne. On the Road with Arya Part II happens as Arya spends most of the entire season making her way to Kings Landing and killing people along the way. since Jon technically died he is freed from his vows and with no longer much love for the Night’s Watch, he joins Stannis. He reunites with Sansa and there is some form of Reekoning. Before they push south, Stannis’s fire magic compromises the Wall. After they leave, winter swallows The Wall and the Night’s Watch with it. While all this is happening, Bran is watching inside a tree or something… doesn’t much matter because his character arc is essentially finished and he’s now some kind of subtle, benevolent magical force. Sparrows continue to flock to King’s Landing and a certain gravedigger with them.
end season 6: danny leaves for westeros. Cleganebowl happens with gravedigger as their champion but not until a reunion of a gravedigger and nobody. Undead Mountain wins and Cersei vows to destroy the Tyrells, but Margery is gone and stays gone. End of the Sparrows. Battle for Winterfell finally happens. Boltons are finished. Jon Stark and Sansa intend to hold Winterfell. Stannis marches for King’s Landing.
begin season 7: danny arrives directly at King's Landing, and easily takes the city. Tyrion has a crisis of conscience and betrays Danny to save Tommen from destruction.Both Tommen and Tyrion die. a completely nervously-broken down Cersei gets Needled in the mayhem. King’s Landing is wrecked and the people put out of their misery since it’s been deteriorating for two seasons. winter swallows Winterfell. Sansa dies forever young and beautiful. Jon flees south.
mid season 7 danny immediately heads north with her Dragons and a faceless Arya to confront the winter threat but is held-up in the Riverlands by Stannis. Epic battle of fire vs. fire mid season. Stannis’s luck runs out with the fire magic and is betrayed by the Red Woman since she’s got a new firey force to join-up with. However, Nobody kills the Red Priestess but sacrifices her nobodyness to do it. Arya reunites with Jon. Jon joins Danny and they find common cause.
end season 7 (possibly feature length): Danny, Jon, Arya and the remaining friends meet winter, Dragons fight and both sides incur heavy losses. Jon and Danny figure things out, R+L=J explicitly confirmed and their marriage restores balance and The Others go home, but not before Danny’s dragons are killed. Arya finally finds her dog and they both return to Winterfell with Arya as the Lady of Winterfell. Tree Bran helps her rebuild. A heartbroken Danny with Jon return to King’s Landing to rebuild and at the very end Danny finds out she’s preggers.