Wrath of Khan easily. Second would be The Undiscovered Country.
Of the TNG movies only First Contact actually felt like a movie to me so it has to be my favourite of those. The others were still entertaining but they felt more like two part episodes of the series rather than movies.
The Abramsverse movies got worse as they went along, going from not bad to awful. Kind of like another sci fi trilogy JJ Abrams was involved with.