Does it annoy you how Photoshop likes to "snap" to the document edges when using the crop tool, selection tools and so on?
Disable Snapping in Photoshop
You can disable this snapping behavior by going to View > Snap to > Document Bounds. Remove the checkmark from Document Bounds, and Photoshop will no longer try to help you out by snapping to the edges of your document.
Disable Snapping in Photoshop Elements
You can also disable snapping in Photoshop Elements by unchecking View > Snap to Grid. When snap to grid is enabled in Photoshop Elements, it is assumed you want to snap to document bounds even if no grid is displayed.
Temporarily Disable Snapping
To temporarily disable the snapping behavior, hold down the Ctrl (Win) or Command (Mac) key as you move near the edge of a document while cropping.