Recently I saw available in a store both Stronghold Deluxe and a Pack containing Stronghold Crusader, Stronghold 2 and Stronghold Legends.
Both offers bear good prices. Stronghold is much cheaper here though. I noticed that S2 is not the Deluxe version and that the S1 version here is not Deluxe.
What I want to know is: What is the better option for me? I mean, if I buy a non Deluxe version, is it upgradable with the same content as the Deluxe copy?
I know that the Crusader Extreme version adds a hell of a lot of stuff that is not freely available to owners of previous version.

I guess that answers the question for S1, thanks... but what about S2 Deluxe? Is the relation the same? In other words S2 deluxe is just a patched up S2 with free stuff added?

Eh, the description I found is quite vague... I cite it here.
"New in the Deluxe Edition
* More maps, opponents, and historical castles to battle! Crusade across Europe in a new game mode!"
It doesn't specify what they are, however...

Yeah, I saw that sort of description too. Guess we will have to wait until someone that actually knows the series passes by and answer. :P
Or I could go and ask in a place like that site you linked before. :D

That's a good idea; the folks at HeavenGames are generally very helpful.

I just asked Mr. Google. A number of pages I visited from there all shared the same information: Stronghold 2 Deluxe is nothing but a patched up version of the game.
So any version I buy will do. I just have to patch it later.

Man... I just want to kill these guys. Really.
I'm totally tempted, but right now I can't. I've got too many games on my desktop waiting for a proper play through and my credit card is a bit overfilled with games this month already.
If I could buy just Stronghold with 25% off, it would be an instant buy, but the bundle raises the price to high up the sky for me (remember 1 Dollar = 2,2 brasilian reais approximately) since Crusader is a bit more expensive. And that package I saw on a store has Crusader too, besides S2 and S Legends.

I have been playing Stronghold a few years now. Here are the differences that I know of:
Stronghold: The Original
Stronghold Crusader: The first sequel, similar game engine as the original
Stronghold Warchest: Both games combined (The first one I bought)
Stronghold 2: A new sequel that was released after all of the above (maybe 2-3 years ago) It features a brand new game engine.
Stronghold 2 Deluxe: Same as Stronghold 2, but includes an expansion pack (with a new campaign etc.)
Stronghold Legends: This game is built on the Stronghold 2 engine and adds Fantasy elements such as wizards and dragons to the game. This is a standalone game, not an expansion.
There is another version that came out about 6 months ago. I think it is the Crusader Extreme you have mentioned. It was built on top of the original Stronghold Crusader game engine (not Stronghold 2) and it was released on the cheap (compared a new release price, not a GOG game price) I think it was around $20(US). What it did was take the old engine and max out the number of enemies that lay siege to your castle. It was meant as an extreme hardcore challenge for people that enjoyed the game engine, but found it too easy on the most difficult level.

Christ... I bought it. Limited time promotions sometimes suck.
I'll keep both waiting in my shelf until I have proper time to play. And most of my games currently installed are properly finished and uninstalled.

Good choice in my opinion.
Stronghold 2 just isn't nearly as good as Stronghold 1 / Crusader, and Legends is even worse than that. Sadly, the Stronghold series ended for me after Crusader.
Paying extra for a bundle with SH2 and SHL is a waste of good cash since you'll probably never finish any of those games out, respectively, pure frustration (SH2) and major boredom (SHL).

Hum... the Stronghold 2 demo was ok to me. It actualy amazed me that wining the mission involved much more than mass producting a single unit (I actually had to mass produce every unit I had. :P)
Anyway, I'm a few games out of the way already, though there's still a large mass of RTSs and a couple of Racing games still on the list. But I've played a little bit of the two already.

I never played the demo, but I recall the first few missions of the game to be OK - until the sheer scale of micromanagement hit me like a brick in the back of the head. I wasn't able to both manage the base and wage warfare on somebody else at the same time after that. It seemed like every time I left the base alone for two minutes to try and prevent my units from being slaughtered on the opposite end of the map, some critical but obscure part of the delicate chain would break and I would zoom back to a keep with population rushing out the doors like there was a plague on.
I'm sure there's a "key" to how to play SH2 and enjoy it, but I couldn't. It was a major letdown at the time after playing SH1 until it was sore and dry - I bought SH2 untested, without reading any reviews, and got a game I never even finished 1/5 of.
That's my opinion.

I seem to recall similar views of SH2 - I think the gave the game too much micro management which is great when your in the castle building mode (one which in the previous games was rather boring since there was not much to do once the basic economy was setup)
However when in the battleing mode it seems to hamper things as one is needed in two places at once - making playing a chor rather than a joy