Well, steams got them CivIV and CivIII on sale, $10 for CivIV complete. But I think I only want one Civ game, either regular CivIV ($5) or colinization($7.50)
 
Can anyone specify what makes the engine different or the gameplay? I know one came out years after the other so I expect improvements in colinization.
 
I might just get the complete pack, $10. But I hate buying stuff on steam I never play, i.e. the Sniper Elite sale, why the fuck did I buy that?

if u get one get civ 4 
it the game everyone loves and the most recent 
 
some do prefer civ 3 but i perfer civ 4

I've got both, and I prefer Civ 4. 
I actually don't know what it is about the new colonization that turns me of it, since I've played quite a lot of the original. 
However I do love Civ4 with all it's expansions.

Colonization is a completely different and (in my opinion) far inferior game. Basically, you have to build several mini-cities is Civ fashion, and build trade routes and caravans and such between them.  You start on the east coast of North America, and NA makes up the entire game map (I think). After that, you have to constantly balance your own expansion against the natives who already live there (they don't want you to take their land). From there, you build up an army and become independant from Europe, which will send a giant angry feet at you. Survive, and you win. 
 
Basically, it's a smaller, more linear version of Civ 4, which are two aspects I really, really don't like. Now, if the option is just Civ 4 or the full package, I'd say the package is still worth it. Warlords makes some good gameplay additions, and Beyond the Sword has more/better music. Fortunately, you can toggle off any of the other changes you don't like (everything else in Beyond the Sword).

I'd suggest getting the pack, really, since you'll probably be so addicted that you'll regret not getting the extra content when it was crazy cheap. 
 
 
Still, if you must only get one of those two, get Civ IV. Civ Colinization is harder and not as fun. Plus, you save $2.50.

Ok, I guess the consensus is reg civIV. I'd get the pack, but I dont think I will ever play the expansions or colonization. I am a very amateur PC gamer, so I dont even know if I will ever play civIV. I played it a few months ago, but since lost the disc I got from my friend. I only remember it looking kinda bad on my 1080p tv, but I'll give it another go I guess.