Star Tropics: Quite possibly one of my favorite NES games of all time. Craptacular controls aside (I need to get a classic controller rather than using the wiimote), its still a fun game. And I had forgotten that old games actually tended to have a high level of challenge, particularly compared to modern games.
also
Civ4: The Civ games are eternal favorites, ranking up there with X-Com for those things I pull out ever year or so and play. But unlike X-Com, the Civ series keeps releasing new versions, which is nice. There is something fun about sending tanks against a civilization that has just developed Knights. Maybe its the meglomaniac in me. Bwahahahaha!