Medieval 2 is the best in my opinion but my favorite will always be Rome. Although you really can't go wrong with any of them.

The original, Shogun.

medieval 2 with the third age mod installed =]

Most certainly Medieval II for me.

Rome and Medieval 2

Rome II will be my favorite game in the series.

Rome. Shogun 2 is probably the worst, so i'd bypass that one.

Rome then Med 2... but once Europa Barbarorum 2 comes out that order may change. Then Empire then Med 1 then Shogun 2 then Shogun 1

I have enjoyed Rome the most amongst the few i have played

Rome. Then Med II. Then don't even buy the rest.

Medieval II, closely followed by Rome.

Rome was perfect, then came medieval II which was rome but better and in a new time period. After that it went downhill. The newer games (empire, shogun, napoleon,...) just dont have the total war feel about them. Lets hope rome II turns the tide!

Medieval II with this mod.

Easily Shogun 2.

Shogun 2.

Rome

edit: i cant pick there all fun

Heart of The Swarm

Napoleon and Shogun 2(FoTS is okay too). Darthmod makes both better though.

Most fun and replayability I've had was with Medieval 2 and the Game of Thrones campaign.

loads of people saying Medieval 2, i have it but never played it, this has made me want to start a game now.

Shogun 2 is a masterpiece, nuff said

Medieval 2.

M E D I E V A L 2 for sur!

I played both Rome and medieval 2 a lot. Preferred medieval 2 myself, although both i had fun with