Yeah, I have a lot of those too. I'm guessing that the "created" date is when you created the folder that they are in, and the "modified" date is closer to being the actual creation date. I know I transferred a lot of files from my old Dell 4100 computer to my new Dell 8300, and a lot of those files seem to have retained their old "modified" dates, but the folders I put them in all have the date I started using the computer. Similar events have occurred since then.