I definitely know how hard it is to get motivated to exercise!! We have gone through ski machines, weight benches, you name it, and they all just sit there. Finally we had to make a conscious decision to make exercise a part of our lives. We put the exercise bike in the living room and rearranged things around it. We then put all the gear - heart monitor etc. right next to it so it's always ready to use.
Now when we wake up and my boyfriend watches SportsCenter before going to work, he gets on the bike. It's not like he "has to exercise" and go off somewhere. The bike is right there, he's in the room anyway. I can ride it if we watch a movie at night.
I really think that's the key, putting the gear out somewhere that you literally have to walk around it <img src="/images/graemlins/smile.gif" alt="" /> If you have an exercise video, leave it in the player and leave the furniture so there's a clear spot to stand. That way it's just a matter of hitting ON and starting, nothing else is required.
Biking and walking are always great, and are perfect family-time activities!