Right click it to Get Info.
Or select it and Get Info from the Menu Bar.
About halfway down the window that opens, you will see an "Open with:" line
Underneath that is a dropdown menu that has a list of applications that should, or can, open that file.
Use it and select the correct application to open that file.
Hit the "Change All" button and you should not have this problem again
Let us know how you get on
Until recently, I've been able to print downloaded documents just fine. In the last week or so, however, they automatically open in Color Utility, which greys out the print command under "File". I'm unaware of doing anything that is causing Color Utility to kick in. I can click on "Quit Color Utility", and it ends, but the next time I try to open a download it opens again in Color Utility. What gives? How do I keep it from automatically affecting downloads, so I can print them again? I'm using Snow Leopard.