None of the movies - not one - to my mind, matched the very best of what the TV series offered in terms of plot, narrative power, and what the cast were allowed to do, or, in other words, good, old fashioned character development.
CGI and special effects and a bloated budget are no substitute for a strong story, compelling dilemmas (ethical, moral, political and military and otherwise), and a good cast allowed to develop their characters, and show their skill with the help of a first rate script. At the end of the day you are telling a story, and everything else should support the telling of that tale - not supplant it, or detract from it, or distract from it.
While I liked quite a few of the original Star Trek - 'City On The Edge Of Forever' is outstanding - some of the very best of the STNG episodes are better than any of the movies from any of the franchises. (And yes, including Star Wars).
In an earlier post,
@ucfgrad93 mentioned "Yesterday's Enterprise" which was an outstanding episode, dark, brooding, menacing, with the cast credibly fighting a doomed and mistaken war they couldn't win.
"Chain of Command" Part 1 & 2 were superb, as were the three episodes dealing with the Borg invasion and its aftermath "The Best of Both Worlds" (part one and two) and "Families" which followed immediately afterwards and dealt with Captain Picard's distress and PTSD.
"The Measure Of A Man" was another superlative episode.