Only Xbox game I've kept is Halo 2 just because I like messing around on Live with friends, but a few other suggestions:
-If you're using the big Fatty McPatty controller (also known as the Duke by many), you may want to invest in an S controller. Friends with smaller hands may thank you if you ever try to do 2-player anything.
-Ninja Gaiden Black is an awesome game, but a lot of people found it too hard. I still had a lot of fun with it, though.
-I love Phantom Dust, but it's not for everybody. If you like card games (Magic, etc.) especially you may want to give this a try. It's $20 new and has Live support, so it's a great value.
-Halo 2 + Xbox Live. I never even played campaign on it outside of a pre-release French leak. Live makes everything better.
