I'm in a very similar boat, and have found that the ten minute work outs are awesome! I can do a couple in a day or do one and go for a jog or something. The flexibility offered by the ten minute sessions has been really helpful for me. And it's always easy to push yourself to do something that's only ten minutes. I used to take longer smoke breaks!
Also, all of the Mommy Got Muscles workouts are 5 - 15 minutes and include a good amount of cardio plus a variety of workouts to keep things fun
Find something you enjoy doing then you won't get bored. I can't keep up with a workout but I can walk my dogs to the park and I love playing soccer with my nephew, these things count towards your exercise. If you want to lose in your legs take a brisk walk around your neighborhood or on your lunch break. Park at the edge of the parking lot, window shop the entire mall before you start going in the stores, or find an activity you like. I like taking pictures on walks so there's always something to see and It pushes me a little further than I would like to go.