filtering using check box

How can I filter records and have all records show up as a list if a particular check box is not checked on the form? Here is the scenario... I have a sub form on a main form. In the sub form, the user will input the current ToDo list of the clients account, notes, etc. If the ToDo is complete, the user will check a check box as being completed. The user also wants to be able to click a button that will look at each and every customers ToDo form to see if the checkbox is checked or not, and if it isn't checked, he wants to see a list of every customer that has outstanding ToDo's to be done.
How do I do this? Please be gentle on me... I'm a newbie and need guidence...
If you would like, you may e-mail me directly at: david@mindinthesky.com
Thanks,
David