Ah, I thought you felt the upcoming sequel was sure to fall short in some way (or felt that Awakenings was sequel-ish, possibly).

Neverwinter Nights: I don't know why but 2 didn't grab me like this one did. The plethora of mods make the choice easy anyways.

Left 4 Dead: Melee weapons in 2? Come on now, aside from the chainsaw, they are gimmicks.

Guild Wars: Prophecies: I maybe in the minority for this but I played all through the life cycle of Guild Wars and felt the game went downhill as the expansions were released. Hit a really low point at Factions, bounced up a bit with Nightfall and then Eye of the North but nothing as 'epic' or wide in scope as the first.

Quake: Atmosphere kills 2 and has the better weapons + feel. 3 has no singleplayer so I didn't like it nearly as much even though it ties for best multi with the first one.

Half-Life: See-saw puzzle, repeat it 20 times and you have the sequel. First one has the better gameplay and 'story'.

STALKER: SoC: Atmosphere is easily the best out of the 3 and has something Call of Pripyat is missing (Clear Sky never happened).

Fallout: 2 was all over the place while the first one was consistent and really refined (well as refined as Fallout can get).

Longest Journey: Sequel was good and all but the first one probably has the best female lead in any game and a really interesting story to boot.

I suppose you expected someone will disagree with this one: I do. Yes, the physics gimmick definitely is overused from today's perspective. Better gameplay - perhaps (though I don't think so). But story? No way. HL is as clichéd as you can get.

But to be honest, the one thing I admire about HL2 is the setting. Valve have poured so much work into creating the universe; every single detail is thought out, and they have polished their revolutionary idea of storytelling through level design from HL to absolute perfection. The ridiculously laid out (On the Rail!) and perfectly generic Black Mesa doesn't even start to compare with City 17 and environs.

(Though perhaps, personal taste might be involved here to a larger extent than I would readily admit. I have always liked the atmosphere of decaying industrial works; and if you ever ride a train in the Czech Republic, and look out of the window - you will expect Combine soldiers behind every corner.)

Panzer General

Left4Dead - levels and actors where more like i would them expect to be in horrormovies, therefore better mood, but i like both

Metal Gear Solid - I agree that it is the best from the "Solid" series (as someone else already said, mgs1 is the thirs game after mg1+2) in terms of full working storyline without stuff thought up as they where going and stuf flike that, so if you have a chance, play that one at least, its a masterpiece
but to be honest: i like to see the series as a whole, that means all games that are canon (msx mg 1+2 (not nintendo versions!), mgs 1-4, portable ops, peace walker), and i like it as it is, best part is, the series is complete as it is now, i doubt that rising will contribute anything to the plot, there is only one black spot, and that can just be said "yeah it happened between mgs1 and 4 and you actually exactly know the important parts of what happened")

Deus Ex

Halo - The first has kind of an PG-13 Schwarzenegger movie appeal to me. The moment Halo 2 brought up ambiguity and that what you are shooting at arent just evil aliens i switched it off and never played it again.

I'll go with Monkey Island, but it requires a little bit of thought.

The first game has visibly aged, it's rather clichéd, but it's special. Very special. It's a work of art, a piece of comedy literature to a Picasso backdrop. It's beautiful in many ways.

LeChuck's Revenge has not aged in the same ways. The modernised interface, music and atmosphere all make it a wonderful experience. It's deceptively short, however. After playing the game several times, I have an almost academic understanding of the game. Besides that play length, LeChuck's Revenge upholds the best atmosphere and introduces the entire mystery of the Secret (AKA: Ron Gilbert's funniest joke).

Now let's examine Curse: Visually stunning. COMI is beautiful and eye pleasing, it's retinal essence is that of pure beauty. It is love. However, COMI begins the devolution of Guybrush's character, portraying him as slightly less cunning and a little slower.

Escape can fuck off. You have the obvious reasons: Control scheme, visual looks, stupid ending. But look a little further beyond that. Guybrush's character has been destroyed. Guybrush has gone from a clever, puzzle solving hero to being Elaine's stupid and haphazard bitch. Escape ruins the character of Guybrush Threepwood and because of its wider marketing (especially its introduction to the PS2), 3D effects and voice acting, that's now who Guybrush is: A stupid bitch. This is not how he was intended to be.

Tales is Escape's redeemer. Telltale portrayed Guybrush as smarter, manlier and heroic-er. Tales does a good job in providing a true MI4 (I'd say MI3, but Elaine and Guybrush are married), by pouring the experience he gains from becoming a pirate from the first 3 games into his character. Tales recreates Guybrush's character in a very good way, whilst still taking on a little bit of stupidity. However, Tales turns the Monkey Island world into a fantasy universe with signs of an establishing lore; Manatee, Vacaylians, further exploration into voodoo. This is the series's weak factor. Monkey Island is not a fantasy novel in the way Telltale imagine it to be. The Trial and Execution of Guybrush Threepwood is the series's strongest redeeming factor, comparable to LeChuck's Revenge in atmosphere and mood.

So whether or not we can say that Secret is the best game of the series is hugely debatable. I wouldn't place it above LeChuck's Revenge, which I consider to be the single greatest adventure game ever written anyway.

OK, so Secret creates everything, establishes the mystery and introduces us to one of the best characters in adventure game history, but is it better than Revenge? It certainly beats the non-Gilbert games tenfold, of course...