I don't have to worry about anyone finding my stash - it's in my closet, no kids in the house, and my wife knows all about it.
In terms of your kids, I think telling them is the best course of action, but ONLY once you're ready for it. If/when you do tell them, let it be known you're sharing your gift with them, NOT some condition or affliction you suffer from. They may not understand it, but how you tell them will directly affect how the news is received. If you show them that you're comfortable with this aspect of your life and it brings you joy, it will be better received than if you're displaying discomfort, embarrassment, and/or confusion.
Until you're ready to allow your family to know you completely (femme side and all), a note with your stash would be a good idea. Write down all your feelings so that they understand that their father was not a sick man, but rather a very normal man who was happy, even though society has a problem with crossdressing.
They're your kids. They'll love you to the end, and beyond. Explain yourself to them in person, or at least leave a note so they can learn the truth about this rather than leave them to their own misconceptions that most people have.
I hope they never have to find the note though. Here's to a long, happy life, Rebecca.
:drink: