How would you tell the difference between some captain and warrior minis? for example, Dol amroth knights and Minas Tirith. They basically seem the same other than poses...so to tell the difference would i be looking at the poses?

Sometimes yes, the captains look very similar to the warriors in the examples you gave. Some people paint the captains a little differently or base them a little differently to make them stand out.

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Pretty much yes - although some captains can thus be easily overlooked in the chaos of battle. Many people therefore choose to make the captains stand out a bit more by painting them differently, either adding decorative trims to armour and clothing, using different colours (red and white often favourites) or swapping colours (e.g. if the Dol Amroth knights have white tunics and blue cloaks, the captain may get the reverse).
As such, many people will also be fine with using a normal warrior model in a different colour scheme as a captain, although preferably somewhat converted as well to further stand out.

The most important thing is that it is clear in game - and looks good!

EDIT: Ninja'd, ah well, an answer in stereo now...

Ah, okay, that makes more sense now. Thanks so much!:)

Regarding the Minas Tirith captain: The newest model of the captain released in the command pack does look quite different now.

His pose is quite heroic with a stone (scratch that, it's a corpse on second look) under his feet, he has a cape and stars on his armour. You can look that up on the official GW site. This discerns him enough from the bulk of the army I think.

For myself I decided that a cape would be the thing determining who's captain for everyone. Thing here is, you need to make that cape yourself with Greenstuff and this could be tricky.

If you only have the basic warriors and don't want to get on capes you can do arm or hand swaps to give them somewhat unique poses. It's quite easy to do with plastic modells. I personally had something I called the 0-2 rule additionally to giving my captains golden helmets. It simply meant, if a Minas Tirith guy has either 0 or 2 weapons in his hand, he's a captain. For example I gave a bowman a sword arm, so he had sword and bow in hans and the swordsman got the empty hand of the bowman, meaning he had a shield and no weapon in hand. The small problem arising is that you then have a bowman with two swords (one in sheath one in hand) and a swordsman with none (because his sheath is empty) but I'd suggest to ignore that if you don't wanna go to a tournament or something.

Isn't that why some of the uniform troops started having helmetless heads of fancy helmets to use as Captains? That would help them stand out too, giving your Captains helmetless heads - it'll look more heroic too.

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