Hi, first try moving ALL files from the Download folder to a temporary folder and see if you are still having the same problem with the Download folder. If the crash then starts on this temporary folder, then its likely 1 or more corrupted files that is causing the crash. You can then try moving 1 file at a time back to the Downloads folder until you discover which file is causing the problem and delete it.
This could also possibly be a thumbnail problem. Try
rebuilding your thumbnail cache and see if that helps. You could also right click on the Downloads folder and choose Properties, choose the Customize tab, and be sure "Optimize this folder for" is set to "General Items" and not "Pictures". Windows may change this back to pictures later. :-|
This also could be a driver problem. The
differences between Safe Mode and Clean Boot is that more drivers are loaded in Clean Boot. Safe Mode attempts to load the most stable drivers. Therefore, this could specifically be your video driver that's causing the problem. Try updating to the latest version, especially if you have recenly got an update for it through Windows Update (look in Windows Update History). Windows Update drivers aren't always the latest version released.
If none of the above helps, write back and let everyone know. Try to give details about what all you have tried and any error messages you get or problems that you have.