Adjust display settings for dialog boxes?

Photoshop thinks my computer screen ( 14" Lenovo Thinkpad, issued by my workplace) is bigger than it actually is, so that in fullscreen mode, the bottom of a dialog box is sometimes not visible, including the "Save" and "Cancel" buttons in the bottom right, among other things. I can't drag the dialog box up because it's at the top of thes creen, and I can't change its size. Here's an example. Anyone know how to change this without adjusting my computer settings to hide my taskbar?