when you install a program on your computer sometimes it forces certain files to open in it... you can change that

 

click

start/run... type in "Winfile"... window opens

click

file/associate... window opens ...

type in the file extension ... example(.JPEG)

the application that opens that particular extension automatically displays... select another one!....select "none" now no one can open  that file!make JPEG's open up in word!  Go-ahead, screw everything up!... no just kidding it's safe, and reversible.

 

and yet... there is another way  and

 

I'd explain it to you, but your head would explode!!... just kidding!  The other way allows you to set particular extensions to open in multiple applications which would be placed on your right click menu but you can just drop shortcuts to those particular applications into your "sendto" folder and you accomplish the same thing