Hiya, Bubbs. I saw your note in the 100+ thread, and sounds like you're off to a great start. Congratulations, and keep up the good work!
I have a wii, and recently got wii fit with the balance board. I also have EA Sports Active 1 & 2, and the regular wii sports game which has things like tennis, bowling, etc. I don't have experience with other game systems for exercise.
I find the wii to be a great way to mix in some different kind of movement from my regular gym routine. In fact, I think I'd credit the wii in general with getting me moving to begin with.
The wii sports pack is pretty basic, but a lot of fun and you can definitely get a little workout from it, especially playing tennis and boxing, both fun with a partner.
Wii fit is awesome. It has a real variety of activities, many focusing on balance and strengthening/toning, and they are varied and fun so you don't get bored. You can absolutely work it in a way that you get a strong strength and cardio workout, or cherry pick to have fun and just do a little movement. The balance board is really key to getting the most out of the program, as everything gets more challenging when you're trying to keep proper form, and it does a good job of telling you if you're off. I highly recommend it.
Finally, EA Sports Active is more like a hardcore workout. It can be tuned up or down for beginners to advanced, and you can vary the inclusion of exercises, length of the program, etc. It isn't un-fun, but nothing in the neighborhood of the wii fit. That said, it can produce a serious workout for when that's what you want. I have had no trouble keeping it tuned just above my ability, and it pushes me very hard. If you consider this program make sure you get the most recent version which has far superior leg and wrist straps that track movement and also measure heart rate to keep you in a proper zone for what you're trying to accomplish.
All this stuff could be considered a bit pricey, but if you can afford it I highly recommend it. Again, it helps keep things varied, keeps your body guessing in a good way, can be very fun to do with a friend or partner, and is convenient as all get out when you want to stay in.
Starting: 11/14/2010, 350 lbs (Yikes!)
Current : 03/31/2010, 295 lbs
Starting:1/20/2012, 335 lbs
Current: 2/10/2012 324.4 lbs
Goal 1: 302 lbs 04/01/2012 April Fools 10% Challenge
Goal 2: 271 lbs 07/04/2012 4th of July 10% Challenge
Goal 3: 247 lbs 10/01/2012
Ultimate Goal 160 lbs 05/31/2013
Lost: 10.6 lbs