Yes, Minister had many crowning moments, thanks to both the marvellous word-play and the skilful performances by Nigel Hawthorne, Paul Eddington and Derek Fowlds; sadly, many tend to lose something in being written down. Nevertheless some shorter ones are still as good, such as:
Hacker: Humphrey! Do you see it as part of your job to help ministers make fools of themselves?
Humphrey: Well I've never met one who needed any help.
Or 'The Skeleton in the Cupboard', when Sir Humphrey loses his equanimity for the first time, when it looks like a very serious cock-up he made earlier in his career is about to come back to bite him in the press, with Humphrey getting increasingly flustered as he tries to prevent the seemingly oblivious Hacker from releasing it:
Humphrey: We'd have to get clearances!
Hacker: Who from?
Humphrey: [Clearly grasping] ... Security implications! Foreign powers, national interests. We have to consult our allies, top brass. NATO, SEATO, Moscow!
Humphrey: Not Moscow. I didn't mean Moscow.
Add to this one, Hacker's pure delight when he eventually cottons on to the reason for Humphrey's agitation, and his realisation that he finally has something he can use over Humphrey, with both Bernard and Hacker barely able to restrain their amusement:
Hacker: The question is, how am I going to deal with it?
Bernard: Well, you could...
Hacker: [Unrestrained glee] The question was purely rhetorical, Bernard.
Yes, Prime Minister has the last five minutes of 'The Key', in which Sir Humphrey's increasing paranoia about being replaced and the increasing obstructions placed on his access to the Prime Minister (most of which, ironically, resulting from his own pompous instructions to Bernard earlier in the episode about persons without appointments or passes being allowed access to Number 10) lead to him clambering out of his window and climbing up a drain pipe, accidentally setting off an alarm in the process. When the bedraggled, upset Cabinet Secretary finally sees Hacker, it leads to one of the show's ultimate examples of Sesquipedalian Loquaciousness:
Humphrey: Prime Minister I must express in the strongest possible terms my profound opposition to the newly instituted practice which imposes severe and intolerable restrictions on the ingress and egress of senior members of the hierarchy and will, in all probability, should the current deplorable innovation be perpetuated, precipitate a progressive constriction of the channels of communication, culminating in a condition of organisational atrophy and administrative paralysis which will render effectively impossible the coherent and co-ordinated discharge of the function of government within Her Majesty's United Kingdom of Great Britain and Northern Ireland!
Whilst Nigel Hawthorne's speeches as Humphrey were legendary, it's also down to Paul Eddington's perfectly played reactions that elevate some of them into the realm of genius; such as Hacker's response to Humphrey's typically verbose announcement that he's moving on to a new job: an utterly nonplussed and uncomprehending "... I see."
Hacker: Don't tell me about the press. I know exactly who reads the papers. The Daily Mirror is read by people who think they run the country, The Guardian is read by people who think they ought to run the country, The Times is read by the people who actually do run the country, The Daily Mail is read by the wives of the people who run the country, The Financial Times is read by people who own the country, The Morning Star is read by people who think the country ought to be run by another country, and The Daily Telegraph is read by people who think it is.
Sir Humphrey: Prime Minister, what about the people who read The Sun?
Bernard: Sun readers don't care who runs the country, as long as she's got big tits.
Suddenly, all those jokes at Fark.com make a lot more sense.
Hacker: Europe is a community of nations, dedicated towards one goal.
Sir Humphrey: Oh, ha ha ha.
Hacker: May we share the joke, Humphrey?
Sir Humphrey: Oh, Minister, let's look at this objectively. It is a game played for national interests, and always was. Why do you suppose we went into it?
Hacker: To strengthen the brotherhood of free Western nations.
Sir Humphrey: Oh really. We went in to screw the French by splitting them off from the Germans.
Hacker: So why did the French go into it, then?
Sir Humphrey: Well, to protect their inefficient farmers from commercial competition.
Hacker: That certainly doesn't apply to the Germans.
Sir Humphrey: No, no. They went in to cleanse themselves of genocide and apply for readmission to the human race.
While we're on the subject:
Hacker: You're blathering, Bernard. Bernard: Yes, Minister. Hacker: Why are you blathering, Bernard? Bernard: It's my job, Minister.
Pretty much the entirety of A Diplomatic Incident, but Hacker's series of facial expressions when he is told of his predecessor's death are a particular highlight.
Also, the entirety of the scene where Bernard and someone else are on the phone. Beautiful lines like this occur: "Yes, we will be wanting simultaneous translators for the meeting with the PM. ... No, not when the PM meets the leaders of the English-speaking nations. ... Yes, the English-speaking nations can be said to include the United States. With a certain generosity of spirit. ... No, you can't have alphabetical seating at the Abbey. You'd have Iraq and Iran next to each other. Plus Israel and Jordan all sitting in the same pew. We'd be in danger of starting World War III. ... Yes, I know "Ireland" begins with an "I", but no. That doesn't make it any better. Ireland never makesanything any better."
("Quarantine, Prime Minister!")
'The Quality of Life', where unbeknown to Hacker, Humphrey has royally screwed him for planning permission for a bank in the area, by sabotaging the minister's visit to a city farm (he ensured it was threatened so the bank could step in and save Hacker's reputation in order to get the permission they needed).
Bernard: [It's] Mrs Phillips, sir...The warden of the city farm you visited yesterday. Hacker: Ah, is she happy with the publicity I got? For her? Bernard: She doesn't seem too pleased. Hacker: Why? Bernard: She's just heard the farm is being closed...the lease is up at the end of the year, and she's just heard it's being turned into a car park. For Inland Revenue inspectors. Hacker: (A little later) This must be stopped. What idiot authorized that? Bernard: You did, Minister. (Hacker is told how he unknowingly did it). And, Mrs Phillips is still waiting to see you. Hacker: She's the last person I want to see. This is the greatest disaster of this century, Bernard! Bernard: There were two world wars, Minister. Hacker: Oh, come on, Bernard. Fighting on the beaches is one thing; evicting cuddly animals and small children to make room for tax inspector's cars is quite another league.
Hacker's brilliant about face and total demolition of a journalist at the end of 'The Moral Dimension', completely bamboozling her and leaving her speechless, and actually impressing Humphrey immensely. The discussion about 'creative negotiation' in Qumran between Humphrey and Hacker also qualifies.
From 'the Middle Class Ripoff', where Bernard demonstrates he may be naive, but he is not that naive, and then perfectly anticipates Hacker's response to a given problem and plans ahead (not included below).
Hacker: I thought these planning inspectors were supposed to be impartial?
Bernard: Oh, really, Minister. So they are. Railway trains are impartial too. But if you lay down the lines for them, that's the way they go.
And sometimes even the guest actors get involved, such as in "A Victory for Democracy" when Hacker solves the pending international crisis the Foreign Office doesn't want the UK to get involved in and neatly shifts the blame on to his Foreign Office Liaison, Luke, who, in addition to not having the British representative at the UN abstain in a vote against Israel, as Hacker had ordered, had been doing his utmost to ensure Hacker didn't know the crisis was brewing. And then, in addition to the blame, "rewards" Luke with a new job as an ambassador.
Luke (suspiciously): Where?
Hacker: Tel Aviv.
Luke (anguished): My career will be ruined! They know I'm on the Arabs' side!
Hacker: It may come as a surprise to the Foreign Office, but you're supposed to be on our side!
This one has a nice little moment beforehand; Sir Humphrey, having had an interest in keeping the Prime Minister in the dark about the situation, is less-than-thrilled when he learns that Hacker has sent a huge British battle group to the disputed region as part of a 'goodwill visit'. He's even less impressed when the Americans, who had been planning to intervene militarily in the disputed region had the British not done so (and cause great embarrassment to the British in the process), announce that they're delighted with the result and are willing to sent 'reinforcements' if necessary:
Sir Humphrey: Reinforcements of what?! Hacker:[Without batting an eyelid] Reinforcements of goodwill, Humphrey.
Hacker realises that Bernard has dropped him in it with Sir Humphrey:
Hacker: (stern) Bernard - how did Sir Humphrey know where I was?
Bernard: Err... God works in mysterious ways.
Hacker: Bernard. I would like to make one thing quite clear. Sir Humphrey is not God. Okay?
Bernard: Will you tell him or shall I?
Pretty much any of the scenes were Bernard points out a badly Mixed Metaphor, but this one is a standout:
Hacker: "The point is, this situation is now a real hot potato. If I don't do something it could become a banana skin."
Bernard: "Excuse me, Prime Minister, a hot potato can't become a banana skin. If you don't do anything a hot potato will merely becomes a cold potato."
Hacker's diary for the episode reads, "I wonder if Bernard ever realises how close to death he sometimes comes."
Bernard gets another stellar moment when he objects to the phrase "stampeding herd of vultures": vultures are a flock, not a herd, and they don't stampede... "What do they do?" the PM asks icily, and unable to come up with a comparable word for "stampede", Bernard just does a bizarre impression of a vulture.
In Big Brother, Hacker finds out that Sir Humphrey's been fooling him, and his wife (Annie) urges him to ring Sir Humphrey. Hacker protests that it's two in the morning, and Annie says that it'll establish his authority. After Hacker's conversation with an audibly dishevelled Sir Humphrey comes this:
Hacker:(hangs up) Oh—damn! I forgot to tell him to come and see me about it before Cabinet.