I like both for different reasons. Star Trek TNG for the storylines. Contrary to what you've just said, I keep on telling people you don't need to understand the tech to understand the story. e.g. Data works well in exploring human emotions and reactions because he doesn't have emotions (at least, not initially). Do you have to understand the phrase "positronic brain" to enjoy the Data episodes? No...
Heheh... have you read "The Physics of Star Trek"? I wouldn't say that the science is Star Trek is based on real-world and possibilities at all. Hmmm, yes... some of the things in ST actually have become reality like the tricorder. (Our PDAs are fast becoming the multi-function, wireless devices that the tricorders are.) But at the same time, we are also very, very, very far away from a range of things... faster-than-light travel, teleportation, inertial dampening, weapons that can be heard in the vacuum of space...
Star Wars and other shows with space battles all guilty of that. Who would watch if there's no sound when space fighters try to blow each up?
Anyway, SW is more of "space opera" than science fiction. The story is basically a fight between good and evil. Just that the setting is in a galaxy far, far away. Unlike most science fiction, SW's storyline is not technology-driven and does not deal with the repercussions of technology nor utopian and dystopian visions. Plain old good vs evil. Which made IV, V and VI a joy to watch.
The prequels. That's another story altogether...