Display wont hold anything but 16 bit

Hi

Would appreciated any help. When closing out of programs
only half of the screen closes. The left closes and the
right half of the screen stays. Same for the background
half of it is white and half of it is blue. I have tried
adjusting the display settings but it keeps going back to
16 bit. Microsoft money sends and error that it need 256
color to run properly. Any help will be appreciated.