I was just reading one of the message boards and saw your post. Honey, you do NOT have the most weight to lose on the sight, and slips are going to happen. I didn't even put my weight in the tracker until I was down to 310. Yes, I said down to. And I am just under 280 now. I've been on Spark since the end of last august (6 months). You can do this. It isn't going to be the easiest thing you've ever done, but nothing worthwhile ever is.
There are tons of exercise videos available on Sparkpeople, including seated cardio, and lower body workouts laying down that aren't killer hard. I've had 2 knee replacements since joining, and I can manage some of the workouts (I especially like coach nicole). Most of them are less than 10 minutes, and they stress to adapt them to your physical ability. Every little bit of movement helps.
I have a Y membership, most of them have financial aid available. A lot of insurance companies and employers are also helping cover healthclub memberships, It might be worth looking into. Pool exercise burns a lot of calories and is easier on your joints.
A great Sparker to check out for inspiration is Indygirl. She overcame a LOT. You may be interested in her team.
Feel free to give me a shout any time if I can help, I still have a LONG way to go and I plan to be on Spark for, well, ever!
Have a wonderful day tomorrow, be kind to yourself, remember- You are and 1249 days ago