i have to be missing something obvious here..
shape tool has recently disappeared, and all i have in its place is a triangle symbol which seems to do absolutely nothing. see image
You have a custom toolbar. To reset to the default toolbar:
Edit > Toolbar > Customize Toolbar > Restore Defaults
P.S. the 'triangle that does nothing' is the Sharpen tool. You can drag it across a photo to selectively sharpen parts of an image.
Retrieving data ...