I've always been fond of Dead Rising considering how much replayability the franchise allows. Heck, it is even encouraged that you played more than once, trying different times each time.
For the same reason, I think musou games also have nice replayability.
Other games include RPGs (Both JRPG and WRPG), first/third-person shooter games with solid content (Gears of War comes to mind, it is always nice to play Horde Mode with a friend), fighting games such as Smash Bros, Tekken or such, and timeless games that put joy into motion; examples I can think are Dead Nation or Geometry Wars 2 (That game about a Knight and a Witch on 3DS as well).







