Thanks for posting that question here. It's definitely a key question to my work here.
The words "Best" and "Good" are very vague when it comes to TV shows.
You mention the commercial aspects of a shows success and that is certainly one way of looking at the strengths of a show. TV does have a specific financial goal as an art form. If a show canÃ¢â‚¬â„¢t attract enough viewers to justify its budget then in the eyes of those who pay for it it will have failed.
However I assume from your question that you donÃ¢â‚¬â„¢t really want to debate the commercial success of Star Trek and Dr Who. Practically speaking both were established in the 1960s when there was less competition in all art forms but particularly in the sci-fi genre. So to some extent their brands have name recognition which has helped their longevity.
So if we move to assessing them creatively we encounter a load of new problems. You mention criteria which includes attracting younger and older viewers. If that is part of your criteria then that is a specific or narrow view of what makes a TV show successful. Shows like Ã¢â‚¬Å“Mad MenÃ¢â‚¬Â or Ã¢â‚¬Å“Breaking BadÃ¢â‚¬Â are deliberately built for an adult audience and wouldnÃ¢â‚¬â„¢t face criticism for not attracting younger viewers.
So it sounds like you might want to debate something more specific like Ã¢â‚¬Å“Why have Star Trek and Dr Who been so successful for so long.Ã¢â‚¬Â In which case their ability to attract younger viewers who then perhaps grow up to encourage their children to watch the newest version would be an important part of their success.
Both Star Trek (particularly TOS) and Dr Who operate on a generally similar basis. In that they tend to set up a new problem or situation each week often involving some kind of moral dilemma. I suppose you could get specific about stories and characters within the show where each show has been particularly daring or successful. A thorough google search would almost certainly bring up academic articles about Star Trek. I remember within the last couple of months the BBC podcast Ã¢â‚¬Å“Thinking AloudÃ¢â‚¬Â had a segment on Dr Who from an academic point of view. If you look in Itunes you should be able to find that episode.
A problem I can see in comparing the two though is that Star Trek is a far more commercially successful series. Of course it is based in a much larger and richer country but you would have to be very specific to argue that Dr Who is the better show. And by specific I mean you would need to argue that Dr Who has tackled a much wider variety of topics or tackled them with greater thoroughness or more interesting perspectives. IÃ¢â‚¬â„¢m sure you could make that case. However personally as a TV Critic I would come to Star TrekÃ¢â‚¬â„¢s defense. After all Dr Who is a BBC product and the BBCÃ¢â‚¬â„¢s charter specifically encourages shows to explore difficult topics while the license fee protects the show from some commercial considerations. Whereas Star Trek had to stand alone in a commercial marketplace and draw an audience or go out of business (as Enterprise did). This means that Star Trek arguably had a greater pressure on it not to offend anyoneÃ¢â‚¬â„¢s sensibilities.
I guess you will have to make up your own criteria in this case. In most shows I watch I argue that the most important factor is believability and the internal consistency of a showÃ¢â‚¬â„¢s universe. One of my favourite episodes of Star Trek ever is the Deep Space Nine episode Ã¢â‚¬Å“In the Pale Moonlight.Ã¢â‚¬Â Having seen season after season of Starfleet officers behave impeccably there was nothing more compelling to me than to see one decide to lie and cheat for the greater good. For me the years of consistency helped create the believable drama of Captain Sisko breaking the rules. I havenÃ¢â‚¬â„¢t seen enough Dr Who to know how this might apply in that case.
That belief in believability and consistency is what allows me to talk about Ã¢â‚¬Å“goodÃ¢â‚¬Â and Ã¢â‚¬Å“badÃ¢â‚¬Â storytelling, characterization, drama and comedy. Unless you have a definition in mind it might be difficult to argue academically about what is better than something else.
IÃ¢â‚¬â„¢ve covered a lot of ground here; I hope some of it was helpful. If you are writing a university-style essay then I imagine you will need to frame the question quite specifically. Perhaps something about Dr Who being more successful then Star Trek at tackling moral questions. IÃ¢â‚¬â„¢m sure you would be able to find other academic articles on this theme to help you.
Let us know what you thinkÃ¢â‚¬Â¦