confused?

Hopefully clearer than my last post.

Created orginally a DVD on my desk top P.C last year with no marks after transfer from camcorder SD card to Windows XP. 'My pictures' into a file called France.
I opened and sorted all 1.4GB of photo's creating folder/file for each area, example; all photo's related to Potiers in a folder/file named Potiers. Once all folders/files completed the France folder was then burnt successfully to a DVD.


Couple days ago transfered the same DVD content to 'My Pictures' on to Laptop which uses Windows 7.

Opened up and found the France folder had a blue dot with white circle and each folder/file inside it has a green dot with white check mark only one has the blue dot and white circle. And all photo's have green dot white checkmark, with about eight (8) have red dot with white x.
these dots appear at bottom left of both files and photo's.

question is what do these marks indicate ?

Blue dot white circle
Green dot with white check mark
Red dot with white x.