Yes if you have not decided based on the people who posted before me
AC1 was fun, and interesting. And to me, it was the most "pure" of the series. As it involves a lot of normal assassinating. But then, it gets stale after a while and the colo palette is really dull.
AC2 changes everything and I mean it. Movement is faster, Ezio is more agile, much more likeable, much more easy to relate to, and the interaction between Desmund and his frens are cool. The color palette is much more vivid than the first game and the environments in which you slay your victims are varied as well.
AC:B is essentially the same as AC2 only bigger and adds a assassin squad at your disposal. Nonetheless, it is worth playing and really fun.
AC:Revalations involved Desmund a lot more but hey, it is cool and Assassin's Creed. By this point of time, the likeable and interesting Ezio will get more and more stale by now. But, it ends off the Ezio trilogy very well in my opinion, and a must-play if you played AC2 and AC:B.
I CANT wait for AC3!!!!! Really want to climb trees and kill dudes with a tomahawk. :3