Can't say about Halo 3 since I haven't played it, but for me Halo 2 > Halo 1.
In Halo 2 you fought in many totally different locations, as MC or as Arbiter. Story is better, gameplay is better, maps are better, graphics are better, more cars, more weapons, excellent multi. Only the ending sucks. Halo 1 maps are bigger, but this is not better IMO and you go through many of the maps twice.







