I feel thy pain, Scott. I'm five foot even, meaning there's not much room for extra pounds to hide. I'm also built curvy (Irish peasant stock) so unlike most women, when I put on a few pounds, it goes to my cleavage and rump first. You'd think that'd be a good thing - but not at my height. It makes me look freakishly disproportionate.
After a heart attack two years ago (a bundle branch block, which is hereditary rather than lifestyle-related), it's been tough to get my daily exercise in. As soon as my heart rate gets above 100 or so, I start getting nervous... which knocks out a lot of the high-impact stuff required for serious calorie burning. And fear ramps it up even further. Couple that with my low blood pressure, and I've passed out cold more than once. Woke up with EMTs strapping me up at a Wal Mart with people leaning over me getting video with their cell phones. Grrr.
However, I've had the good fortune to pair up with a very handsome fella who happens to also be a personal trainer and physical therapist. He's got a better bod at 48 than most 20-year-olds, and he's been giving me some extraordinarily helpful tips on proper weightlifting work that have really helped me tone up. (The fact that he's a gorgeous beast and he likes my cooking just means I work extra hard at getting back into shape, lol - bonus points!)
The key for me has been slowing down and not trying to do it all at once. Cardio work, then light lifting, focusing on three standard simple machines to work on a strong core. I always thought it was super-complicated; turns out it's easy, just don't fall for the "you need ten different machines" hype.