The special effects weren't very special and the costumes were rather bright*. These are the sci fi television series I grew up with**. Or at least, the ones first broadcast before I was born***. I watched many repeats.
This list doesn't claim to be the best of old science fiction. I know there are some famous ones missing, but I kept it to those I enjoyed most. They're ordered by date of first broadcast, with the oldest first.
1. The Twilight Zone
Date of First Broadcast: 1958
Created By: Rod Serling
Premise: Freaky dark stuff happens. Be afraid.
Ramblings: The earliest on the list is also the most atypical. Each episode was a separate storyline, often with dark and twisted endings. If you think you've got a unique twist ending for your story, the Twilight Zone probably did it first.
The stories tended toward the psychological, rather than action. Some were social commentaries. TV censors hadn't cottoned on that science fiction could be used to comment on real world issues, so the Twilight Zone merrily (or not so merrily) got away with it.
The Good: Thoughtful plot lines and a willingness to break new ground.
The Silly: It was a tad over-reliant on twist endings. Which worked when the series was fresh and new, but some of them haven't aged well, due to being used countless times since then.
2. Doctor Who
Date of First Broadcast: 1963
Created By: Sydney Newman, C. E. Webber, Donald Wilson
Premise: The Doctor comes from an alien race called the Time Lords. He travels through time in a TARDIS, which happens to look like an old police box.
Ramblings: The early Doctor Who episodes tended to have plots which took many episodes (often a whole series) to wrap up. The Doctor, and his various companions, would have adventures in the past, future and on alien worlds. The special effects were awesome BBC explosions (awesome compared to having no explosion at all).
It's hard to sum up the whole run of series, as there were many Doctors and many plotlines. I liked the Tom Baker era, and his companion Romana (also a Time Lord). I tended to like the alien and future episodes best, but there were some fun historicals too.
The Good: The fluid nature of the series meant creative storylines.
The Silly: During the Jon Pertwee era (when the Doctor was stranded on Earth), synthesisers were all the rage. They added a synthesiser sound to everything. Mysterious object hits the Earth with a thud... with added synthesiser. Doctor hits his elbow on something... more synthesiser. It's like giving a toddler a music box.
3. Lost in Space
Date of First Broadcast: 1965
Created By: Irwin Allen
Premise: The Robinson family head into space to colonise Alpha Centauri. But it all goes horribly wrong, and they end up lost... with a deceitful doctor and rogue robot along for the ride.
Ramblings: The first series tried to have plot and continuity. After that, it gave up trying. But it kept the silly right up to the end. Lost in Space is a classic for its silliness, but it lacked any attempt at long lasting themes. I remember it for the robot, more than anything else.
The Good: It had a robot.
The Silly: When Mrs Robinson did the laundry, why did she haul the wonderful future clothes washing device outside? Especially as it only took a few seconds for it to clean, fold and wrap the clothes in cellophane. And on that note, if I had a future clothes washing device that wrapped all my clothes in plastic, I wouldn't be happy. I don't want to unwrap my clothes in the morning. I want the throw them on and go.
4. Star Trek
Date of First Broadcast: 1966
Created By: Gene Roddenberry
Premise: In the distant future, Earth has formed a large Federation of planets with other peaceful alien races. These are the adventures of Enterprise, the flagship of the Federation's fleet.
Ramblings: Most people have heard of Star Trek. It's spawned many spin-off series and films. The series combined entertaining fluff with social commentary, appealing to a wider audience than programmes like the Twilight Zone. The upbeat view of the future was appealing. The idea of Earth as a nice place to live, with the chance of becoming a space explorer, can't be beaten.
The Good: The way it snuck in serious themes. A few episodes still got banned, but they got away with the rest.
The Silly: That fuzzy camera filter whenever an attractive woman appeared, just in case you'd missed the fact she was attractive.
5. The Time Tunnel
Date of First Broadcast: 1966
Created By: Irwin Allen
Premise: The time tunnel is a time travel device, built as part of a secret government project. Two scientists go through the tunnel, but there's no way to bring them home.
Ramblings: Time tunnel wasn't big on accuracy, either scientifically or historically. The stories were fast-moving and entertaining, as long as you weren't expecting something serious.
The Good: Having the people in the present watching the travellers was a good dynamic. It let the viewers know things the travellers hadn't figured out.
The Silly: Despite being thrown through time randomly, they'd always land at some major event in history. What are the odds?
6. The Prisoner
Date of First Broadcast: 1967
Created By: Patrick McGoohan, George Markstein
Premise: A former British secret agent is held captive in a mysterious village.
Ramblings: This series is famous for the quote "I am not a number - I am a free man!". Everyone in the village had a number, with the main character becoming Number Six. The village was a strange and surreal place. Anything could happen. The story followed Six's attempts to escape from the village, and find out what was going on.
The Good: You never knew what would happen next.
The Silly: Those big floaty white bubble balls were the silliest. But I liked them anyway.
7. Land of the Giants
Date of First Broadcast: 1968
Created By: Irwin Allen
Premise: A space plane flight goes horribly wrong, stranding the crew and passengers on a mysterious planet. Everything on the planet is huge, including the inhabitants.
Ramblings: This series had all the stereotypes. The dashing captain, the lazy/deceitful fat man, the cute boy and his dog, the fairly inept female characters in short skirts. It was fun, in that cheesy kind of way.
The Good: I liked the feeling of being tiny in a huge world. You can't beat a few giant paperclips.
The Silly: I could mention how Valerie always kept her yellow outfit so beautifully clean (whilst wandering around drain pipes). But the real problem was mathematics. The scale of the little people to big people changed as the plot/special effects demanded it.
8: Space: 1999
Date of First Broadcast: 1975
Created By: Gerry Anderson, Sylvia Anderson
Premise: The moon is knocked out of orbit, sending it on mighty space adventures. Along with the people living on it at the time.
Ramblings: Even as a child, I found the setup rather tricky on the suspension of disbelief side. It's easier to imagine a spaceship with a special engine than a moon with no apparent propulsion (other than the initial explosion). Still, they had adventures, and that was fun.
The Good: Living on a rogue moon wasn't the most usual of ideas at the time. It was appealing, if not very plausible.
The Silly: For a moon knocked out of orbit, it was moving terribly quickly. This is the secret of faster-than-light travel. Just knock yourself a moon out of orbit and hop on board.
9. Battlestar Galactica
Date of First Broadcast: 1978
Created By: Glen A. Larson
Premise: The Cylons, a robotic race, wipe out the twelve planets colonised by humans. The surviving ships form a convoy and set out for the mythical planet of Earth.
Ramblings: The convoy of ships was a neat setting. It could have been used more, rather than relying on finding a new human colony each week. Overall, it was good fun. The space battles were with single one person fighters, making for more exciting fight scenes. I liked a lot of the characters, which wasn't true of all the sci fi offerings of the time.
I liked that the Cylons weren't the fault of the humans. The 'humans make advanced robots who wipe them out' plotline is rather common. Less common is for an alien race to be the ones capable of making the robots, getting wiped out and leaving their legacy behind.
The Good: The colony/wagon train dynamic worked well. The rich tried to hoard the food, the former inhabitants of the different planets had different cultures and didn't get on, and the civilians retrained into professions needed by the fleet.
The Silly: Triad - a ball game played by the crew. It isn't the game that's silly. It's the costumes. It looks a lot like underwear, with kneepads and a hat. I couldn't take it seriously as a child. I still can't.
10. Buck Rogers in the 25th Century
Date of First Broadcast: 1979
Created By: Glen A. Larson
Premise: An astronaut (Buck Roger) is frozen in space. Centuries later, he's revived.
Ramblings: By this time, the honeymoon period of colour television was fading. So were the costumes. White and neutral colours were the theme of the day.
Buck Rogers was given a lot of responsibility for a guy cast forward so many centuries, with no clue what was going on. But it had lots of shooting stuff and action. There was wish-fulfilment angle here, that someone from the present day could end up in the future having adventures.
The second series included more serious themes. It also didn't have great ratings and got cancelled. I liked the serious side though. My favourite character, Hawk, appeared in this series.
The Good: I liked how the scientist was an old guy wearing a cardy. Most present day clothing didn't survive to the 25th century, but the humble cardigan made it.
The Silly: I like robots, but I didn't like Twiki much. His voice was just too silly.
* Shortly after colour television came along, there was a period of "oh yay, colours". And so they added in as much colour as possible. Everywhere. The more it clashed the better! The future was definitely not white and silver.
** Live action only. Cartoons would confuse things a bit. And puppets would be a whole list on their own, just with Gerry Anderson.
*** 1980. This might seem arbitrary. It is. However, a quick look showed that the number of possible listees mushroomed hugely after 1980. It's as good a cut-off date as any.