I'm experiencing a similar problem. For example, right before I came to this forum, I had CCleaner do a run:
To Be Removed: 51.4MB
Removed: 814.5MB
I've also noticed that during "Analyze", CCleaner is not(?) doing an analysis of the custom folders I have set up for deletion. However, in the few folders I do have set up, there was not 750MB of data (for the previous example).
I am using CCleaner 1.40.520 and WindowsXP Home.
Ihave CCleaner set up to do a 7-Pass secure file deletion.
As far as checkboxes go, I have the "default" boxes that are established when CCleaner is installed, and I also have "Custom Files and Folders" checked.