I voted for Nemesis, but I feel that a word needs to be said about Generations which could have been a bigger hit.
First, I like Generations. It's not the best of the TNG movies but it is neither the worst. Malcolm McDowell is a good villain actor and he made Soren credible as an individual who, at one time, was a good person but become addicted to the false reality of the Nexus. Picard ruminating over his career path and the decisions he made in lieu of having a family was also a good touch. I like that part of the story and having seen that, despite Picard's success as an officer of the line, he had his personal regrets.
The movie was going good right up until Kirk appeared and the damn thing went off the rails. Captain Kirk chopping wood and making breakfast for his girlfriend? Picard is telling him that there is danger going on and that he is the captain of the Enterprise and Kirk is too busy caught in his false reality and looking for toast. I know, I know, you can argue that the Nexus had overpowered him but this was Kirk...the guy who could talk computers into blowing themselves up and who didn't like to lose. I found it unacceptable that the Nexus would fool him so easily. It wasn't until he rides a horse and jumps a ditch that he wakes up.
And, finally, Kirks death. It will continue to be a point of discussion for years to come on these boards, but we all know that it sucked. The only acceptable Kirk death, for me, was on the bridge of a starship making a difference. If the creators, Berman included, had intended to destroy the ENT-D then why didn't they put Kirk on the damn ship? I kept wanting to see the last seconds of his life as he stood on the bridge of a starship with sparks flying around and crap blowing up as he knows that, this time, he is going to die. Throw in some moving music, perhaps a montage of past scenes throughout his life, and ka-boom.....a hero's death. Okay, maybe it's a touch on the corny side but it would have beaten Kirk dying on a piece of scaffolding that Soren failed to fix during the last OSHA inspection. Ronald Moore is a good writer, but he flopped badly with this one and it totally blew the emotional impact of the movie.
/endrant