Windows Movie Maker - Free and reliable - Did I mention that it's free?
Though you might have a little problem if have Movie Maker 2. That's because version 2 doesn't recognize DAT files. You'll have to convert them to WMV files first. The plus side - size of the files will be reduced. And you can add whatever music/sound you like.
Hi Guest we just wanted to alert you to a major change in the forum. We will no longer be allowing the posting of outgoing links. Please use the attachment feature to attach media to your posts.