I don't have much time to play, but when I do, I prefer Dos Equis. Seriously though, complex strategy... as I've gotten older, I generally don't like mashing buttons anymore.
Favorite games/series all-time:
PC - Crusader Kings 2, X-COM, SimCity, Civ, Madden, NHL, Lords of the Realm, Red Baron, Oregon Trail
Arcade - Mortal Kombat, Golden Axe, Gauntlet, Rampage, 1942
Sega Master System - Ninja Gaiden, Rambo, Altered Beast
NES - Tecmo Super Bowl, Blades of Steel, Punch-Out, Mario, Tetris, Zelda, Duck Hunt
Atari - River Raid, Knight Rider