Biking to Work
This might not be the best for those of us living a ways away from work but if you live in a city you have to consider biking to work. Not only do you tone your legs but you save the environment by not driving your car and you get healthier every day when you head to work.
You want to ease into it so you might not want to bike to work every day but this is a simple exercise: Bike to work. You leave your house on your bike, end up at work on your bike. Repeat to head home and sit down on that couch to relax and take a load off.