Playing fetch with your dog is good exercise; don't underestimate it. Any time we get off our bums and move around we are doing our body a favor. There are lots of quick, little exercises you can do before you even get out of bed--like a few easy-does-it crunches and stretches. You can do some easy-does-it squats in the kitchen while waiting for the tea (or whatever).
Go through the SparkPeople exercises and look for those ones that are simple and don't need equipment. Look for the ones you can do at any moment of the day in the middle of doing other things. What you are looking for here is a bit of muscle strengthening and improved flexibility not iron-man competition...LOL!
I frequently drop to the floor while in the kitchen and just hold the plank position for about 20 seconds, raise my middle up to the yoga position "downward facing dog" then lower my middle (slowly) all the way down to "upward facing dog" breathing long and slow all the while I'm doing this. Takes less than a minute. If you are totally unfamiliar with these yoga terms look them up on Google or find them here in the exercise list. Doing this little exercise a couple of times a day will amaze you with the strength you receive from it.
I also keep a pair of dumbbells kicking around the house that I pick up and use for arm and wrist strengthening...while waiting for the "whatever" to boil--ALWAYS keep butt tucked under for this or any lifting exercise.
These are just suggestions to let you know that you can get started doing very easy things that don't interrupt your day.
And then of course, you came to a very good team for learning how to feed your body so that it can respond to your desires for health.

Hospitals are terrific for traumatic care; for acute care. They do a really, really good job in saving lives when it’s a sudden bleeding emergency. But in terms of chronic care, they’re terrible; in terms of the illnesses that most people have, endure, that cost the most money, that last the longest and ultimately die from. -Dr. Andrew Saul