Sudden Unexplained Waste of Space/Storage on Machine?

Hoping someone can help me decide (from the two screenshot attachments);

1. If I should delete or do anything about these "Recently Changes" searches files/folders under "Username>Searches>Recently_Changed";

and;

2. These thumbnails are being "SAVED/STORED" on my machine, in my Windows Picture Gasllery, all of a sudden. Again. this seems to be a USELESS taking-up of space on the machine (which I think Firefox 5 is causing?).

Thanks in advance,
glenn...
PS - I ADDED TWO SCREEBSHOTS

 

Bah, don't think it is firefox. But, have ye run ccleaner to clean up some misc files?

http://majorgeeks.com/CCleaner_Slim_d4191.html

 

Bah - yeah...religously ... couple, three times a week...?

 

Are these duplicates files?

 

Not sure how to determine that, but that is my impression...I mean,I "KNOW" I already have "some" of these stored/saved elsewhere...

 

I no longer understand the world...if others have "mind-reading" powers, well, more power to `em, but I, do not . . . . . . . . . . . . . . . . . . . . . .