If you're going to be doing weights
instead of cardio, at least make sure that you do something to get yourself warmed up. I'm no fitness expert, by any means, but I'm fairly certain that if you just start lifting on cold muscles you run a pretty high risk of injuring yourself. Even marching (or dancing, or jogging) in place for 5 minutes would be better than nothing. Not enough to wipe you out, just enough to get your muscles warm and your blood flowing. And don't forget your stretching.
Have you ever tried circuit training? I imagine it is something that could be adapted to your living room fairly well. You do a short period of in-place cardio (enough to keep your heart rate in the target zone), then a short period of weights. You keep going back and forth. It seems like, for toning, it's the best of both worlds, and is sometimes easier (in my experience) than just going full out on a treadmill for 40 minutes. And more fun. That's basically what the Curves gyms are based on.
Otherwise, have you ever tried any of the old work out videos? I'm almost ashamed to admit it, but I LOVE the Richard Simmons Sweating to the Oldies series. They're so much fun! And there are people on there who look like me! Or bigger than me, even! I've also got my old standby, Jane Fonda's Favorite Fat Burners. It's easy to adjust intensity when following those videos, so that I don't end up panting or feeling week.
Good luck, and let us know how it goes!
- Dayna