re: Limitations of Windows Explorer
Your question may already have been answered, but I suspect your image files (e.g., JPEG, TIFF, etc.) are associated with Photoshop. Windows Explorer uses PS to generate thumbnails (even if you are viewing folders/files in Tiles, Icons, Lists, or Details mode).
The solution is to right-click on an image file type, select Properties->Photoshop Image tab->uncheck the Generate Thumbnails box->Click OK.
This should apply across the board for that image file type and should clear up the problem.