Hiding doesn't help at all, whatever is in the file can be read in one way or the other.
"Save for web" allows you to adjust the quality and also the amount of EXIF data to be kept. If you select "No metadata" in the dialog box (CS4 here) then the image will be stripped off everything. The other way is what catchlights mentioned.
Of course, a quick google for "Forum" would have told that this is an online discussion site. But I guess some smart people are just too good at going around chanting "search google, you lazy bum!":angel: