The ones I've played in order of my preference:
Empire Earth (IMHO best I've played ...see below)
WarCraft III (Beautiful artwork, great storyline)
StarCraft (different races are very very well balanced)
Age of Empires 2 (Great game...should have been better. Waay to much micromanagement)
WarCraft II (fun fun gameplay)
Age of Empires 1 (fun but the interface is a bit clumsy)
WarCraft (still a respectable game but the sequels are better)
Homeworld (low on list just becuase I've not played enough to form opinion)
C & C Generals (good graphics, sh1tty gameplay, downright racist)
Why I think EE is the best:
This game is what AOE2 SHOULD have been. The rock-paper-scissors balance between units is perfect. There is NO "Ultimate" weapon. There is no strategy or tactic that doesn't have a counter. The scope of the game is unbelievable. It's like several games in one. Those of you that are fans of AOE will make a relatively easy transition to this game.
The designers got rid of several annoying facets of RTS's. Resource piles never run out - but there is a maximum number of units that can mine at once. You are forced to expand to grow more powerful, not because resources have been exhausted. Citizens and many other units are intelligent enough to keep themselves busy at times. You DONT have to keep replanting farms - this was a silly rule in AOE - it forces micromanagement for no good reason. You do NOT have to build more houses to raise your population cap..another annoying rule. Houses have a different purpose
If you are a fan of "building" this game is for you (random map/standard rules). If you are a fan of "combat" this game is also for you (deathmatch/tournament rules). You can easily play this game with 600+ units in your civilization and not be burdened or overwhelmed by micromanagement. You can treat buildings as units including grouping them, setting multiple waypoints and such. The ability to add actions to the queue of units is awesome. You can tell a single citizen to do the following: repair something, move somewhere following a series of waypoints, repair something else, build a town, a tower, some anti-air + 20 other buildings then go over here and collect resources. You can then leave the citizen be and when you come back he/she will be busy mining after completing everything you asked.
My complaints about EE:
Formations - units use formations but fail to hold them when moving in mass. AOE does this better.
AI - fun to play against but it downright cheats at the beginning. I think this was a shortcut the designers used rather than forming a good set of opening moves at the beginning
The expansion - Added a lot of features to multiplayer (buddy list etc) but was otherwise useless. The space-ages it adds done much better by StarCraft.
Warcraft III is a VERY close second choice for me. Blizzard does their typical job of producing finely polished game.
Generals - what a crock of Shiz. The interface to control your units is pathetic. It's almost as dated as WarCraft 1. The graphics are nice and all but the nail in the coffin is the racism. Sure its supposed to be kinda funny but so is any other racist joke so HA-HA and F*ck you. It seems to be written for 12 year olds...which makes the negative influences even more damaging.
If you like AOE 1&2 you owe it to yourself to try EE. AOE2 is a great game in it's own right but I think you'll like EE better.
gawd this got long..