Running is one of the best things you can do to quickly increase your fitness level. It provides a great cardio workout, and burns fat faster than just about anything else you can do. The problem for most of us is... where to start? Starting with a walk/run program where you are walking more than you are running, then gradually ramping up the ratio to increase the running time is the best way to get started - and the least intimidating.
There is a great article on Runner's World that gives an 8 week program to do this - I highly recommend that you check it out and give it a try. You may even find that you enjoy running!
~Noah
