Kinect Sports and Dance Central are definite highlights and Kinect Adventures is fun and surprisingly polished for a pack in title. I can personally recommend Kinectimals, especially if you have children or young people around to play and Your Shap: Fitness Evolved is fun and easy to play. Kinect Adventures comes with a few demos on the disk, and several more can be found in the Marketplace.

My three are Adventures (which I guess everyone has), Dance Central (for my wife, I swear!) and Kinect Sports.  My next game will be Your Shape and after that, I think I'll have to wait like abHS4L said.  Speaking of Kinect Sports, before you play volleyball, make sure you can't jump and reach your ceiling fan.

I would totally go for Dance Central.

#1 lots of fun and you feel the burn the next day
#2 it has a work out mode when you click on "Perform it"
(actually counts Calories, that's kinda cool)

Doug Monroe: Your Shape is not the greatest. Word of advice get the ACTIVE one, worth the money: It comes with blood pressure monitor for your wrist  to help you in your work out.

Doug Monroe: Wife: I do not recommend Biggest Loser. The work outs are not the greatest for the beginner (if she's a beginner)
The leg work on Biggest loser is the OPPOSITE of the trainer's movements.

Which means if they have their LEFT leg in front and they SAY use your Right leg. It means: Use your RIGHT leg, but on the screen you'll see their LEFT leg, very confusing.

Disadvantage to Biggest Loser I found: No Muscle Burn soreness the next day. Not like Dance Central. I love Dance Central. Now I want them to come out with one for Country Line Dancing, and ZUMBA.
That would be a workout, then I could freaking rid the gym forever.

(Because with the Active, Dance Central you can incorporate weights in your routine)

You NEED to get The Gunstringer! It is amazing, so responsive, and so much fun. I also highly recommend Child of Eden. Such a beautifully made, and addictive trippy little game. I'm shocked they haven't been suggested yet.