I cannot view videos I've downloaded. When I download a video, I double click on the file in the SHARED folder and get this message, "Could not find the aplication that created this document. To open document select an alternate program, with or without translation." But this only gives me Acrobat Reader as a choice. What do I do?

It depends on the file type. Some you can't, avi's hang it up. Not worth the work. Anyway back to your problem in the messsage window, uncheck the box for Show only recommended choices. All your apps will be there for you. Try Movie Player for starters.