Well, I really enjoyed ODST when I beat it on my first play-through on Heroic. It was the first Halo game I played to where you don't know everything just be playing the first mission. I was slightly disappointed that you couldn't dual-wield, but it makes more since now. I mean, I'd like to see anybody here control two shotguns perfectly without any strain. Really ODST's only had two major flaws that I saw. First- you couldn't go to Firefight on the Halo 3 maps. Second- NO BATTLE RIFLE!!!! WTF!?!?!!?! :P
Well, now off ODST, I didn't really like Halo 1 that much. All the aliens just seemed the same to me. In Halo 2, aka-the best one, I didn't like multiplayer, but I loved singleplayer. In Halo 3, I hated singleplayer. It was a disgrace to both Halo and Bungie. Multiplayer was pretty good though, I guess. Wish you could have chosen a game to join like CoD4 style instead instead of random people or friends only.
So overall, I love Halo. There could be much better games, and I'm not saying that they're my favorite games, but compared to most other games out there, Halo is like apple pie to blueberry pies. It's just better in sooooo many ways.......well.....cut singleplayer......