If your New Year's resolution is to get in shape, Wii Fit is a great place to start. Many people dread a workout, but this "game" manages to make that life-extending goal not only more achievable, but also something to look forward to doing every day or so. It's not a traditional game, but it never promised to be.
It's well worth checking out, whatever your age or current fitness level. Some may malign the lack of true multiplayer, but without multiple Balance Boards, it'd be hard to pull off properly anyway. Regardless, if others want to join the fun, simply revert to those antiquated notions of "sharing" and "taking turns."