URGENT--Need to supress "Do you want to Open or save this file" for (CSV AND DOC FILES) in IE 8, IE 9 on Win XP and Win 7

Hi 

In our Task in Salesforce we generate one CSV file and one doc file after one button click on salesforce screen. we need to download these two documents without the popup message "Do you want to Open or save this file"

Pls suggest Registry Edit Option Or any IE browser configuration or anycode to get rid of this popup as this is very critical for our Task. 

Thanks

Kartik