If your interested in huge RTS games the total war series of games is unbeatable...
if leading an army of ten thousand to crush your opponent and leave thousands of dead strewn across a battlefield just leaves you with a fuzzy feeling... then this is the game! (one of the many ones midieval II is my personal favorite)
http://www.gamespot.com/pc/strategy/empiretotalwar/index.html?tag=result;title;0
That one is going to be the best game in the total war series
http://www.gamespot.com/pc/strategy/empiretotalwar/index.html?tag=result;title;0
http://www.gamespot.com/pc/strategy/rometotalwar/index.html?tag=result;title;2