Fire Emblem Awakening - very accessible and fun SRPG with tons of free add-on content everywhere you turn. Should have co-op for you guys.

Etrian Odyssey IV - very good if you want a pure dungeon-crawling, party-customizing RPG. There isn't much story to string you along and the first bit is a tad repetitive; is easy to lose interest and it's not for everyone. Check out the free demo on the e-shop, though (Oh yeah play demos!)

As you might expect, Super Mario 3D Land is a delightfully magical game.

New Zelda coming out next month! Bravely Default, essentially Square's return to Playstation-era Final Fantasy, is coming early next year. Enjoy!