In figuring out where to start, it's important to determine whether you are organizing (setting up systems so you can find what you need when you need it), or SHEDing (decluttering, which is a process that helps when you are in transition, and unsure of where you are going next).l

If you are organizing, (and reading Organizing from the Inside Out), the best place to start is a SMALL area in which you spend A LOT of time, and that you can complete in 3-4 hours.  Perhaps the front entry, or the bathroom, or your linen closet, or pantry.  Completing that first gives you a chance to practice the steps of organizing, and you will feel the benefits every single day as you quickly access what you need for daily living. 

If you are SHEDing, you want to start in a LARGE area in which you spend the LEAST amount of time, and to which you have the least attachment to the items. This could be a spare bedroom closet, or your pantry, or any space that has a large quantity of items that are clearly obsolete.  This too, can be a project that is completable in 3-4 hours.  By completing this area, you will create a large iopening of space, and energy which will fuel you for your next project.

Cleaning up in 10-15 minute bursts of time is neither organizing or decluttering.  It is cleaning.  And while it has it's place, in my expereince, does not provide the sense of completion or results that reward you for your efforts or transform your life.

The trick, whether organizing or SHEDing is starting with a project that is 3-4 hours in duration from start to finish.  You'll jumpstart your progress, and as Joli described, gain so much momentum, that you will methodically be able to tackle the rest of your home.